I want to do maximum damage with the spec, talents, and glyphs that I'm most comfortable with. I may switch a talent up if I am stopping to heal up, or respec a pet to tank on the fly, but I'm going to plow damage with SV.
I am going with a different set of Glyphs for leveling.
Glyph of Mending - to keep my DPS pet killing
Glyph of Camouflage - sometimes its easier to get XP from quests and skip the mobs
Glyph of Marked for Death - for fast kills (I normally have this one)
I'm also going with the Glyph of Fetch. I spent a long while trying to get a macro to work smoothly with my play style, that didn't get hung up in weird ways, and that didn't require me to turn on auto looting from the general menu. Here is all that in one macro:
/console autoLootDefault 1
/run if not _Y then UIParent:HookScript("OnUpdate",function() if _Y>0 and GetTime()>=_Y then _Y=0 SetCVar("AutoLootDefault",0) end end)end _Y=GetTime()+5
/cast [@target, exists, dead] Fetch
Now if you normally walk around with AutoLoot on, then you can go with a much simpler macro and forget about those first two lines.
Because there is real time between when Fetch is cast and when the loot window comes up you need to have a delay. Getting any sort of delay logic into a macro is convoluted at best these days. It took me three hours to figure out the issues, crawl down dead ends and get it all to fit in 255 characters. I hope you enjoy.
I recommend you keybind your new loot command to something easy to hit. For me, that's F2. Here's a simple view of it working.
Oh! and if you're in a group with group loot on, you'll need to target a lootable corpse instead of just the last one you targeted.
Edited to add: Slightly newer more verbose video of it working.