Will give you some idea of possible offsets. I think 45mm offset on a 5.5" rim will work just fine. Probably even look a bit better, especially in the rear.
I think wider rims, even with the skinny tires, might be better. I'm thinking of going to 6.5" wide rims in 45mm or so offset, probably in 16" or 16" diameter to keep the wheel weight low. Probably will opt for 185 or 195mm tires though next time. The stock 175mm is a bit too skinny, I think good for fuel economy, not so good for traction...