Need Help with planning the places to visit

Hi

Passengers:
Just me and my wife (26 years of age - so not that old considering if we have to visit a lot of places - we can do it)
Following is my plan to stay in the Switzerland area:
23 May (Monday): Arriving by day train from Paris to Zurich (Reaching by late afternoon 2-3 PM)
28 May (Saturday): Leaving on a day train from Interlaken to Venice (Leaving in morning)
PS: I am also open to suggestions about how to leave for Venice - either from Interlaken or Zurich depending how the below itinerary spans out.
So in between these, I intend to visit the places that I know of:
Mount Pilatus
Mount Titlis
Jungfrau
I am not aware of any other famous places that I need to cover.
Also I would be more interested to visit scenic beautiful places.
So can you please advice me on:
(a) How should I be planning my stay at Zurich / Lucerne / Interlaken depending upon the 3 major spots that I want to visit being - Mount Pilatus, Mount Titlis, Jungfrau ...
(b) What other places I can visit in the surroundings of Zurich / Lucerne / Interlaken considering I am there from 23rd Afternoon until 27th night (leaving on 28th morning) ...
(c) Any other tips/suggestions about the overall stay - hotels deals / travel passes etc ?
Thanks
Sunil

How about the Reichenbach Falls? It's a series of waterfalls on the River Aar near Meiringen in Bern canton. It's where Sherlock Holmes, apparently dies at the end of "The Adventure of the Final Problem" locked in mortal combat with his arch nemesis, Professor Moriarty.

The end of May is often a good time for any waterfalls as there's the most melt water coming of the high mountains and glaciers. This year may not be quite as good as other years but it should still be the best time of year.

Meiringen also has a claim to have been the birthplace of the meringue so you can try them as well :-)

Easily reachable on public transport from the Interlaken area.