My ideal playlist setup:
Competitive:
Arena
Team Slayer (Noble DLC required)
FFA (TU only, DLC required, more oddball)
BTB (Equal Objective/Slayer weighting, Noble, Defiant Required, TU)
Infection (Would do away with this in a heartbeat, but realistically its there to stay)
Combine Snipers and Swat (would piss their respective pops off, but eh)
Squad (All DLC required, basically the new DLC hopper ala Premium Battle)
Community:
MLG
Action Sack
Grifball
Omitted:
Multi-team
Double team
Squad DLC
Invasion
TU ZB Slayer
All but one of the Anniversary lists
Annnnnnd, basically have Anniversary playlists combined into one 4v4.
I'd imagine that, assuming people don't get pissed off and leave Reach forever, that should increase the population of each a fair bit. 11 in total. It would be great to trim it down to 9 by getting rid of playlists that were formerly DEXP weekends.