It's not that simple to just test on one track. Some tracks will work better with a 205 vs 225, others the opposite. Same general thing with the overall contact patch provided using a 225 on a 6" vs 7" rim. For handling tracks, I'd sure take the 7" rim. I know a while back Tom Fowler from OMP Motorsports had done some testing at Road Atlanta using different tire widths. His conclusion was that the wider tire (225s) provided the best results.

Do you think there would be a difference between a 5" and 6" rim? What about a 4" and 6" rim? I'm sure the graph wouldn't be linear, but there have to be points on it where the gains and losses hit more. Even for the sake of perception, ITB drivers will feel the need to purchase the wider rims. It sucks for existing racers in ITB. I too came from ITA and understand that this wheel change makes it more complicated than just swapping out an A for a B using vinyl.