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There is nothing to see at Lauterbrunnen. It's just the starting point of some of the most expensive Swiss mountain railways (Jungfrau, Schilthorn).

All places you mention can easily be visited in day trips from Berne (if you sleep in a hotel or hostel close to thre railway station). But with this solution, you sit 2 to 5 hours in trains every day, more if you go on by train from Lauterbrunnen to Jungfraujoch or from Zermatt to Gornergrat, etc.
But frankly, I wouldn't do that. Sleep at Lucerne, Zermatt, Montreux, etc. and start day trips from there:
steamboat ride from Lucerne to Vitznau and cog railway to Rigi;
railway, cablecar or cableway (gondola) ride from Zermatt to any mountain and short (or longer) hikes to glaciers or mountain lakes;
panoramic train from Montreux to Gruyeres and Broc with visits of the cheese diary, the castle, the medieval town and the chocolate factory,
steamboat cruises on Lake Geneva, may be up to Prangins castle (Swiss National Museum), Nyon castle (Porcelain Museum), Thonon-les-Bains (Bellegarde castle and Ripaille castle)
etc. etc.

SCENIC SWISS RAILWAYS

Almost every railway ligne through Switzerland is scenic. Here are the best ones (in this order of priority):
Glacier Express Zermatt-Brig-Chur-St. Moritz, Bernina-Express St. Moritz-Tirano,
Golden Pass Montreux-Gstaad-Spiez-Interlaken-Lucerne, Voralpen Express Lucerne-Rapperswil-St. Gallen
Old Loetschberg line Berne-Spiez-Kandersteg-Brig, Simplon line Brig-Domodossola-Arona, Centovalli line Domodossola-Locarno,
Gotthard railway Lucerne-Airolo-Lugano-Chiasso,
Mont-Blanc-Express Martigny-Chamonix-St-Gervais (-Geneva).

http://www.myswitzerland.com/en/home.html
http://www.swisstravelsystem.ch/en/
http://fahrplan.sbb.ch/bin/query.exe/en
http://www.rhb.ch/Video-Glacier-eng.784.0.html?&L=4
http://www.rhb.ch/Video-Bernina-eng.782.0.html?&L=4
http://www.rhb.ch/UNESCO-Clip-eng.1061.0.html?&L=4