Good ole reliable timing belt Audi 4.2 things last for hundreds and hundreds of thousands of miles, and in a big C5 Avant. In the US we didn't get those heavy bolstered recaros, just sport seats. Car looks like it will be a amazing daily driver for you or anyone that plans to buy it from you. I'd suggest a transmission fluid and filter change as something on the top of your list. That little (well quite big at 320lbs compared to the 6 speed 01E weighing 160lbs) ZF5HP19 needs good maintenance. Looks great! Good color combo aswell.
I always feel its a great shame that these wonderful machines fall into the hands of people that just don't appreciate them for what they are. The thought of just stapling the headliner because it was sagging is such a bodge job.