What I would like to see In forge is,
probably that you could add Brutes, Elites, Grunts etc(other than Spartans).
Also I think It would be so cool to
be able to change the weather to like,
snow, raining, hail storm, blizzards etc.
and Maybe have a bigger budget so people can buy more things.
Although I do think that the budget they have In Halo 4
Is pretty good but, some people dont think so
so, Id like to see It change so not as many people are complaining.