Going by the rest of your projects, what about an EP95 Starlet?
1.3 NA 4wd as standard, but identical mounting points to the 1.3 turbo lump... which in turn shares alot with the 1.5 paseo block.... potential for a 1.5 turbo 4wd beast
Personally, id get the feature @ 400, then just enjoy it!
600bhp civic wouldnt be too difficult though!
What about a torque monster VAG derv to keep daily driving comparatively cheaper?
Its not a poor comparison to compare a modified 350z to a standard E46 though..... although my point was more about the fact that RWD cars are harder to push to their limits if its something your not used to.
If it helps...
I traded from a 350z (similar performance to an M3) to my current 197 cup, on the roads I drive daily a clio is a much more accomplished car. Added to the fact that I have much more confidence pushing a FWD car than I do a RWD car.
Different strokes for different folks...
I think if i was to get rid of the clio, an Integra Type R would be the only option if i was considering a "similar" car.
IMO M3's are awsome cars... running and maintaining one isnt so much fun though