When we've needed repairs on ours (cracked glass after skiing accident), we've sent ours by FedEx across to a company in the US called
http://www.iphone3gscreenrepair.com/
We tracked the parcel on the way over. After being signed for at the repair place, it was fixed and re-shipped back to us the same day.
This was after we'd previously contacted the Apple reseller in Zug, whose idea of a solution was to sell us an Apple refurb model as a replacement instead of fixing the current one; it's just not something they do.
If you were going to set up a similar service in Switzerland, I'd be cross-checking the prices of these other places, checking out how quickly they turn things around (if you can offer the same, that's great) and also checking out which specific repairs they offer.
G