I think its nice. It reminds me a lot of Halo 3 Rumble Pit but I also want to be able to play on the maps that were already built in the game like Haven, Solace, Adrift, etc.
Please 343, bring in an FFA playlist with these options:
-Community maps mixed with original maps
-More gametypes like KOTH or Oddball not just Slayer
And I think that’s it for me.
They are going to put them in a playlist with the original maps. They are just allowing us to test out some of the best forge made ones. They’ll toss the ones we don’t like, make some tweaks, and then deliver a finished FFA mode.
Going to be fun. 
Most of Halo 4’s threads belong in the “Matchmaking” and “War Games Feedback” section. This one included, I believe.
On-topic, I agree with all of your suggestions and I am loving the gametype too 
This belongs here:
https://forums.halowaypoint.com/yaf_postst197331_Community-Forge-FFA-Feedback.aspx
Thanks!