Seperate team settings would be fun.

OK this ideas mainly because of reachs firefight customs. In it we could customize both elites and Spartans separately. The Ability to do this was great for setting up versus matches with friends and made it so we could make the Spartans defensive the elites offensive or reverse or keep them equal. Its a nice ability and its been bugging me. Why was it never in invasion, or team game types in general.

Having separate team settings would make defensive game types even more fixed on the objective.
Give the offenders things maybe higher shields or better speed or even different forced weapons

you get the point
nice to have
easy to add (I would think but im not a game designer yet)
and would add to customs