If u go with 18"s, 265/35 and 285/35 would be an ideal combo.
For the 19"s, I'd go with 255/35 and 285/30, the M3 GTS size combo. Then again, the wheels you are going to get is 0.5" wider than the GTS one in both F&R, so 265/30 and 295/30 should be good too.
I have 19" te37s in the exactly same spec as your OP, running 255/35 and 285/30 with no problem. I am also lowered on KW V3, no rubbing at all.