OOOOh! Sorry to be the optimistic one always disagreeing with you about your vents.....'cause a vent is always legitimate if it is what you feel! BUT...
I think the different colors could be fun! Sometimes the same number of each color is what people expect...so to do something different will be fun and "wild"

You could do things in a trapezoid pattern of 3 in the front line; two in the middle line to the outside of the three; and four in the back line.... and then do a "pyramid" of 2-3-4; reverse the trapezoid....... then you could do a little dance off, where each group is one "street team" and they play off each other.

Use it as a challenge! Good luck!