Would it be bad to have 38 offset on the front 2 wheels and have 35 offset on the back?

It would not be bad. The half inch wider rear wheel adds 7mm to the offset.

Are you looking for a visual aesthetic or are you looking for handling improvements on the track? What you have to look at is tire clearance rather than wheel size. Scrubbing your fender wells in not good ever. I would test fit them and put a load on the vehicle to check for clearances.