Like Kichi says, a humbucker will always sound a bit louder and balsier then most single coils.
If you keep the single coils in your guitar, I think a VHII would be a good option. The VHII performs well in bolt-on Fender-type guitars and can handle drive/fuzz/distortion very well (great rockpickup), but cleans up great too, to a near singlecoil-like quality. It's a very dynamic and articulate pickup and delivers the punch.
If you want to replace all pickups, a VHII + Mothers Milk would be a good option. For funky stuff I would pick these, or perhaps Sultans. I guess you want to play funky stuff with the singlecoils. A humbucker is not really suitable for that.