How about Lausanne (LSGL), north side of Lake Geneva it has customs but be careful with size and nature of the paved runway - it dips. Bex (LSGB) along the Rhone Valley with a grass runway. The best of the lot has to be Sion (LSGS) further along the Rhone Valley. It has customs and is a combined military/civilian airport with a long paved runway. For weather look at
www.homebriefing.com which will give forecasts for all of the major Swiss valleys