Quickplay should have literally every 4v4 mode available in the playlist and you should be able to choose which modes to include in your search (like MCC match composer and Call of Duty quickplay).
This way people will be able to choose the modes they like without low population playlists ruining their chances of playing those modes.
So add stuff like Team Snipers (S7s Only), Skockets, Ninja Slayer, Fiesta, etc. into quickplay and allow us to choose which modes to include in our quickplay search.
Then could also streamline the rest of the playlists too.
Add Team Snipers (S7s Only), Skockets, Ninja Slayer and Fiesta to Social Doubles and allow people to choose which modes to include in search.
Add Skockets, Snipers (S7s Only), One in the Chamber and Escalation Slayer to Rumble Pit and allow people to choose their modes.
Fold Big Team Social and Big Team Battle into one playlist and allow people to choose their modes.
This way we would only really need to have a few social playlists since people will be able to pick which modes to play within each playlist (This would also help people complete their challenges more reliably).
Quickplay
Social Doubles
Rumble Pit
Big Team Battle
Tactical Slayer
Weekly Featured (Infection, Grifball, etc.)
Then with Forge, Customs Browser, more Ranked Playlists and a couple new dev made maps every season the game would be pretty set for content. Then the only remaining big problems (if not fixed by then) would be desync, network problems, bad matchmaking, cross core, etc.