Aug 16, 2016 - 3:23 PM
Hi Yogigirl, welcome to MySwissAlps!
You'll definitely be able to enjoy lots of outdoor activities in Lucerne and Grindelwald. I don't know the Seilpark myself, but I think it's worthwile if you're looking for such an active vacation. Further tips, including paragliding activities in the Jungfrau region, can be found at www.myswissalps.com/ac tivities/sports.
Bern wouldn't be my first pick if you're looking for sports activities. Another mountain location might be better in your case, or simply extending your stay in Grindelwald. If you do want to switch base towns, there are lots of options. I think you're right in skipping St. Moritz as it would require a long train ride for such a short stay. A town in the Rhone valley, as you've mentioned, might work indeed. If the vineyards are what you're looking for, I'd recommend the Lavaux area rather than Sion. Montreux or a nearby location would be great in that case.
An 8 day Swiss Travel Pass certainly makes sense if you expect to travel quite a lot. Please find details at www.myswissalps.com/sw isstravelpass. Retailers are listed at www.myswissalps.com/sw isstravelpass/price. An online purchase is recommended, as you can simply order a print at home pass which allows you to start traveling right after arrival in Zermatt.