New to site but not to Audi

Hi all,
Just joined the site on the recommendation of a friend of a friend. Just changed my 1998, 163000mile 1.8 A4 Avant for a 2005, 2.0T A4 Avant and am finding it difficult to love. My old car was like a comfy pair of shoes. Even after driving brand new hire cars & pool cars from work with significantly less mileage and more technology, I was never dissappointed to get back into my old faithful Avant. It was never the greatest handling car in the world but I get my thrills on 2 wheels so thats not important. It was just a good way of getting me to work & back in crap weather and for transporting kids, dogs & camping gear on weekends away.
I changed the car as I wanted an auto box, a bit more power and now is a great time to buy (bought for 2k less than the trade price)!
At present, I wish I had kept my old car. I am happy with the multitronic box, although I am averaging 30mpg, with 200ps or so, that was expected. The problem is the handling.
The new motor has 17" alloys with low profile tyres and the ride is shocking. The car tracks at the slightest ripple in the road and crashes through pot holes like they are open cast mines. Can I rectify this by swithing to 16" wheels and bigger profile tyres or is it a characteristic of the newer cars? The tyres are probably a budget brand as they were fitted by the dealer so maybe a decent set of quality boots would help?
Also, has anyone found any decent quality replacement wiper blades without paying Audi hundreds of pounds??
Any advice welcome.
Thanks.
Mark