Not trying to be argumentative here (damn, first post, dont want to get on the wrong foot!) but i am a little confused in regard to why you so strongly say 16x8 +/-0 wheels are entirely inappropriate on E30s, and yet you will say to people that 16x9 +15 with 3-5mm spacer is okay. Using the Wheel Offset Calculator, the difference between 16x8 +/-0 and 16x9 +10 (effective w 5mm spacer) is actually +3mm further out for the 9" rim. But you do not tell people it won't fit?
I ask this because i've just bought myself an E30 and really want so aggressive wheel fitment. That said, I dislike the look where the front wheel is poking more than the rear. ideally i want maybe a 5mm-ish of rim poke on stretched tyres. I am looking at running coilovers all round (GC or KW probably) and have been eyeing off the likes of Kerscher Carmonas. I really do not want to run a 3-5mm Slip On, and i feel anything thicker will push the rim out too far. As such i am (sadly..lol) considering the 7.5 +20 up front with a 20-25mm spacer and then the 9" +15 up back. Sound reasonable?
Also when you say fitment up front, what type of camber are you allowing for? I assume aftermarket camber tops and maybe 2-3 degrees?