Depending on what functions forgers have to use, what custom games are you guys thinking of doing?
Personally, i can see me making a batman arkham style custom game with PV.
I am also looking forward to making a proper city. Reaches budget was so low you could barley make any customarily built towers. Also building a ship would be on my list.
As for game types, I can see games with everyone in mantis’s, but i’m looking forward to see what other vehicles we will have. Although i’m looking forward to seeing what the mammoths can do.
I’m definitely making a Slayer variant with DMR/AR spawns, weapons, AAs and powerups on map. And maybe another one with the Speed Boost powerup by default.
I’ve always loved weird and wonderful games like where zombies are invisible and the humans have sentinel beams/ focus rifles 
I wonder is you could put down a flood skin/ armor effect for people to use, or force people to be flood even in non-infection games? 
Almost an Alien vs Predator sort of game. Maybe no Aliens but there would be Predators.
For a Predator Promethean vision or Camo for the AA choice and a weapon I haven’t decided yet.
While for Humans they get Sprint (well default duh) and Thruster Pack perhaps and a Shotgun and AR.