The reason I played NFS before was for the exotics, the latest ones don't have any of those, so I don't really enjoy them. Although, I did play NFSU, and it was fun for what it is, but it should not have been part of the NFS brand. If they had simply called in "Underground" or something, it would have made more sense.
If they are going to make a new NFS, it should be a real NFS, with crazy exotic cars. If they want tuning aspects, then have it so you can construct your own exotic-class vehicles. Instead of having the "Obnoxiously Ricer" body with the "Glowing Red" brakes and the "Compensation" spoiler, have the "Carbonfibre Monocoque" body with the "6-Piston Ceramic" brakes and the "Venturi-Effect" spoiler system. I think that would make for a much more enjoyable experiance.