Two small improvements that I would still like to see in QL:
1) [x] Sound in Background toggle, so I know when the match starts while I'm tabbed out. Because these fuckers take ages to F3 sometimes. This should really be standard these days, every game has it.
2) Spectator queue for team modes. Surely it would be a step up from everybody just spamming or holding down team red/blue binds. Duel already has it, just imagine teamsize >1, and it is exactly the same thing.

Now, I know, Steam QL isn't supposed to get any more updates. But these two things would be incredibly easy to implement, IMO.
Whatever...
Where is Sync & Sponge nowadays? They still oversee QL on Steam and have access to it, don't they?

Ya I'm sure I could think of many more improvements, but what would be the point... these two stand out as they'd require so little effort to code, yet hugely improve quality of life.
What's on your 'wishlist' ?