I agree with jimc's comments. 28mm tires are a lot smaller than 35mm and will require running higher pressures so your comfort level will go down considerably. Rather than drop a good chunk of change on new wheels plus tires why not put some good 28mm slicks on the ones you have now and see how you like them?

Also as rhenning suggested, if you want a race bike just get one. The N+1 concept has merit.