The competitive side of Overwatch wasn't available for very long and I didn't participate as much as I probably should have. I only played two games twice there. They were great games and people cooperated and I came out with 100% wins. But in two of the games, the other side had someone drop and nobody replaced them, so it was a bit bogus. The non-ladder games had player problems, but nothing that severe.
But without further ado, here are my reactions to the maps.
Watchpoint:Gibraltar (ESCORT)When attacking, I really like a hero who can stay on the payload. The team does need heroes to take care of snipers the whole way through. I'll sometimes take that role. But I generally prefer Lucio. I use the payload as a shield. I can float right over it to avoid fire. My ranged fires being made from the payload are great visual "callouts" to the team where I see enemies flanking. Being on the payload is also the best place to use Lucio's ultimate. Mercy and Soldier:76 are also fine choices but are a little more reliant on the team. Of all the maps, I probably have used the widest selection of heroes here as they all can work well.
When defending, I prefer to have a mostly front head-on attack hero. I have amazing fun with defending with a sniper or Pharah in the hangar room. There are beautiful nests there as well as being up on top of the ship. Overall, Widowmaker, Hanzo, and Pharah are my favorites there unless a healer is needed in which case I find Mercy to be ideal on defense as she can get to everyone and use that to stay out of harms way. Of course Mercy needs to do that proactively or she's toast.
I had hated this map for a while as it came up randomly way too often. Overall it's a pretty good map that can appeal to most heroes.
King's Row (ASSAULT then ESCORT)I really like this map because there are a lot of terrain and access points that are not clearly obvious. It does have plenty of choke points, but they aren't terrible. The architecture is nice as well. There are two poor things. 1) Defenders without a teleporter for the Assault phase have a long of a run back to the fight. 2) The defenders home from the Escort phase has two doors, but unless the attackers are already in the room, you only want to take the right passageway.
When on attack, I absolutely love Widowmaker. She starts in a freakin' perch. You of course don't want to start the fight right there or you'll be insta-glib'd but give it a few heartbeats and you can take out the counter-snipers and then rack up a few more kills from extreme range before jump grapling hook to the next ledge and next and next. At the initial start, if someone already has selected a sniper, I'll go heals or an offensive character who can deal with the inevitable Symmetra sentry turrets or Torb turret.
After our attack team moves to the Escort phase there are a few more sniper kills to be made from the top hallway which has windows facing both directions. Then all the defending heroes will be in most of the same locations. This is conversion time from Assault to Escort is always a good switch time if: a) it makes sense as a counter, b) your ultimate isn't close, c) the momentum loss isn't a factor.
When on defense, I really like Torbbjorn or Junkrat. Ultimating as Torb is great fun. I think many people do it only to mega-boost their turret. I certainly will time it that way, but I'll also make sure to have full ammo, not be near my turret and run for their tank and healer firing the short (secondary) powerful shots. I've run through may Reinhardt shields and shot their backs before they realize they need to drop the shield and swing. Junkrat is next on my personal fun list. Then a counter-sniper. Then Symmetra.
Numbani (ASSAULT then ESCORT)Numbani is an abandoned city battle with streets, buildings, balconies, and upper walkways. I absolutely love Junkrat for Numbani offense or defense. Clearly I play him differently for each, but there is a ton of terrain to work flanks with. I've also used Torb and I want to use Mei a lot more. Tracer is also brutal to defenses even when she's properly dispatched. The defense respawn points in mid-game are nasty. And I've used Bastion with a good group -- but in a typical PUG he's not great alone.
Dorado (ESCORT)I'm not sure I have a favorite for this on offense or defense. I've had good luck with most of the heroes, but none really stand out. I would say I switch a lot. I've had good luck with Bastion on the last defense line. But Junkrat on the middle defense. If I'm not switching a lot on this based on phase, I'm probably playing Mercy or Lucio. Both are great, and I'd pick between the two based on who else is in the group. Note: I'm not a big Zenyatta fan.
Hollywood (ASSAULT then ESCORT)In the initial stage when attacking, I prefer to go with Widowmaker to counter-snipe and take out a Bastion. Then I'll look to switch to a Pharah for the western set and movie studio. I should add that the last phase of Hollywood has the main terrain features incredibly similar to the last phase of King's Row. The payload moves in the same and there are similar access points up and around. The up part of that phase is why I like someone who has quick adjusting access to those points.
In a defense position, I love those higher access points for a final defense. For the initial Assault defense, I'll really like a Bastion set up to obliterate a first wave of attackers. The trick with Bastion is to set up, eliminate folks, and move to another great position. Bastion has good spots but they have to be cycled through. It will also depend on how and where your fellow defenders are operating. I have had some rather amazing wipe-the-attackers on Hollywood when I'm sitting in the attacker's flank and counting to ten before opening up. I'll switch for defending the Escort somewhere in the second phase. In that second phase, I've had a few great games where I sit Bastion on the payload and ride it back to the starting gates. But that can require a helpful tank.
Route 66 (ESCORT)This is my third-favorite map. I love how it looks. I love the kitch. I just don't love the slog of pushing the payload. This is a very counter-oriented map. Maybe it's more like counter-counter-counter. Each role can be greatly effective or ineffective based on the opposition. Long range, short range, air, ground, etc. I will almost always take Pharah on attack if there isn't one. And on defense a sniper or Pharah if there isn't one. But all of that can be countered quickly by not being a particular counter to anything (more useful to counter something else) or removing the need for the counter. The slog comes out with the run-backs. I don't play a lot of Soldier:76, but I probably should for this board. His long range single click is dead accurate -- you just need to tap it instead of continuous fire. His payload movement is great. His heals are great. There are a limited number of vulnerably placed health packs on this board. Otherwise, McCree would stand-out more. In a nutshell, I want to love this map but find the heroes alway a little lacking. And there is an Ultimate cost to hero switching. Maybe this is the tank-lover map?
Temple of Anubis (ASSAULT)My selections on defense for this are similar to King's Row. It is made of two somewhat horrible chokes to assault. I've played the full mix of heroes here. Because of the choke nature, some tanks aren't the best, especially if they simply help charge up the ultimates of the enemy. I have seen it played a lot of ways, but the most common is a solid defense well in advance of the first assault and a more bunker-command defense on the second assault point. This tends to mean that combo'ng ultimates for the second assault point is how attackers prevail, and counter-ultimating on the second assault point is how defenders hold out.
Hanamura (ASSAULT)On defense, I'll always start out with a Torb and turret near the main wall to the first point. If there's a Torb already, I'll do a healer or Bastion set up in front of the first Assault point. If there's already a healer, I may do a Symmetra and turret up the side building and upper gate access points. Symmetra's portal is always nice if you want to hold your defense at phase one.
On offense, I may take D.Va. She can rocket through a gate defense and make a joke of small turrets. Plenty of other damagers are useful for the same type of access but they don't have her health. She's also good for a quick left hand air strike to phase two while forces are reeling from phase one. If phase two is protracted, switching to someone who can be johnny-on-the-control-spot is important. Vision is also quite important to the team as turrets are likely and in many different configurations. Taking a Hanzo may not be ideal for eliminations but team information is pretty important. Widowmaker has a great perch on top and on the sides of the gazebo right outside the main door, but then entering to claim the objective is next to impossible and you won't get as much vision uptime as Hanzo.
Volskaya Industries (ASSAULT)This is my least-favorite map. It's a mostly choke point and ultimate coordination game. The second assault point is more than the first. It's not particularly fun. Anubis has similar aspects as does Hanamura. But this is worse.
There are some tricks you can use as an attacker though. For the first Assault, as Pharah and possibly Lucio, Winston, Reaper, and D.Va you can go to the far left of the board instead of the first chokepoint. You can then rocket jump to the landing area beyond the death sea. From there you can skirt around to the Assault point. You can do something similar for the second Assault point. You can go up the right side and rocket jump to the stairway.
On attacks I'll often use Pharah as we can expect at least one if not two turrets. On defense I'll often be a turret maker or turret. That said, Pharah's ultimate has to be combo'd with a decent ultimate otherwise she goes down if she uses it from the air. Pro tip: Use Pharah's ultimate with partial cover instead of hanging in the air vulnerable from all sides -- unless you're combo'ng it with a stun or slow ultimate.
On defense I'll try and hold my ultimate to counter if it's a useful counter. I also enjoy participating in the turret war.