Well, first I think we should consider what type of game Polyphony is trying to create. If it's meant to be a street racer, then PD should go to
http://autos.yahoo.com/newcars/ and
http://uk.cars.yahoo.com/newcarguide.html, pick the top spec one or two in each category (i.e., Civic Si & Type-R, Audi S4, etc.), throw out the trucks, mini-vans, and SUVs, add some classic muscle and ALMS-era non-race-modified (och, the old Alfa Romeo's were just awesome) cars and call it a day. About 200 cars in all.
Or is PD trying to make a whacked-out, ridiculously fast racing game? In which case go to
http://www.supercars.net and call *that* your day (McLaren F1, Bugatti Veyron, ad nauseam). 500+, I think.
[Whether GT should include rallying is another thread altogether.]
Or is Yamauchi looking for a true encyclopaedia to draw upon? Honestly, this idea interests me the most, except that it might be unfeasable in the near future (and I very much like the idea of GT4 being in the near future).
I've got my short list of picks (100 or so, heh), but that's *my* favorites and not everyone else's. What I'd reccommend PD do is to
balance things. What all versions of GT have lacked is balance in the selection of cars. Yes, in global sales Japanese cars are probably dominant, but not in people's hearts. How many of you are driving Saturns & Civics but yearn for a Porsche or M3? The disparity between the lone 328i and eight Skyline's PD included is shameful. I'm not saying one is better than the other. The varied motorsports prove what's what. What there should be is equal ground. M3 vs. Supra; Clio 172 vs. Civic Type-R; HSV GTS Supercharged vs. Skyline GT-R. Just because Yamauchi is surrounded by rice-mobiles, doesn't mean that's what the rest of the world is like.
Sorry for the lengthy post. I've just read through 16 pages of posts and a lot was on my mind.
BTW, the "pro-shop tuning" and "body shop" ideas rock! And slightly off-topic, but does anyone else think the Nurburgring should be included?