My core BoM team has been:

IC R Magneto w/ Inspiring Command
V Pyro w/ Trick Shot
V Avalanche w/ Construct (<- although Black Tom may take his place)

This leaves plenty of room (at 300) for figures like Exp Sabretooth, Scarlet Witch. On paper, it doesn't look like a particularly threatening team...but with proper use of Barriers, it is possible to get multiple RCE and BCF hits against opponents without them able to do anything in return.