Here is my tentative itinerary, request your suggestions/additions/modifications.
7th - Arrive at Zurich ~8:30am. Store luggage at Zurich airport Metro and proceed to visit Rhine falls. Come back to Zurich airport and head for Lucerne.
Sightseeings in Lucerne to be done over the 3 days - Chapel bridge, Water Tower, Old town Lucerne, Dying Lion Monument, City wall, Lucerne Transport Museum.
8th - Visit Mt. Titlis (depending on weather), explore Lucerne for rest of the day
9th - Mount Pilatus -
10th - Leave for Lauterbrunnen and store luggage at the station.
Hike to Stechelberg. Check into hotel at Wengen and spend remaining day to explore Wengen
11th - Depending on weather - Hike to , than take train to Jungfraujoch from Wengen (if weather is not good to be done on some other day) and hike from Kleine Scheidegg to Mannlichen [Can return ticket can be purchased from Wengen to Junfraujoch and back to Kleine Scheidegg?, Also the ticket from KS to Wengen for travel once or can be done multiple times?]
12th - Hike from First to the Bachsee (Please suggest what additional specific places can be explored on this day)
13th - Lake Brienz boat tour and Giessbach falls at Iseltwald. Can Lake Oeschinensee be done instead? Or pls suggest any other excursion for this day.
14th - Proceed to Montreux in morning through Golden pass line from Interlaken
Store luggage at Montreux station and proceed to Vevey and than change for Chexbres village. Spend time doing walking tour at LavauxVineyards (Any vine tasting suggestions?)
Head to Montreux, collect luggage and proceed to Geneva.
15th - Catch TGV for Paris
Have gone through the forums and understand that STP will be more beneficial. Not considering Bernese Oberland regional pass as travel from Interlaken to Montreux will not be covered. Am i correct? (I know there is a different forum for questions on railway pass, didn't want to open a new thread hence posted my question here)
Thanks for your help.