well...the grafics are a big part of a game but not more then about 40% if creating a game that should work with 2007, id sugest trying to make some thing with very detailed grafics, peaple wont to be able to make there stuff persenal. changing hair, modefying the fases of the character, stuff like that.
so if your really really wont to make this game good, id sugest you not to host it untill you have some thing that many many peaple like.