Below is our itinerary for an upcoming trip. Most of the time will be spent in the Jungfrau region. I've been researching the Swiss Pass, the Jungfrau Centenary Pass, the Jungfrau Unlimited Railways Pass, and just learned about the Swiss Half Fare Pass. All the options are quite overwhelming. Any advice is appreciated.

4 People:
2 Adults
2 Youth (19 year old)


Fly into Frankfurt
Day 1 : Rent car, visit Karlsrue and Oberammergau. Sleep in Oberammergau.

Day 2 : Neuschwanstein and surrounding area. Travel to Interlaken
Option 1: Drive car to Interlaken and turn it in there
Option 2: Turn the car in at Zurich and take train to Interlaken
(Probably not much difference. save a little in the rental dropping it off in Zurich,
but then have to get train tickets. Driving will have gas expense).

Train from Interlaken to Wengen where we will be staying 4 nights

Day 3, 4, 5, 6
All Jungfrau region
Lauterbrunnen
Grindelwald
Kleine Scheidegg
Murren
Schilthorn
Jungfraujoch
Trümmelbach Falls
Hiking trails

Day 6 Night: Travel to Rome via train
Interlaken to Domodossola
Domodossola to Milan
Milan to Rome (sleeper)

Day 7, 8: Rome

Observations:

Swiss Saver Pass (200.00 per youth, 225.00 per Adult)
This was my first option. It would cover the Day 2 trip from Zurich to Interlaken if we decide to return the rental car there. It would also cover the Switzerland part of the Day 6 travel to Rome. In the Jungfrau region we would get 50% off Shilthorn and 25% off Jungfraujoch and Kleine Scheidegg. I think all other destinations are valid. The 2 adults could get the Saver Pass and the other 2 could get the Youth Pass.

Jungfrau Centenary Pass (225.00 per person)
This seems to go everywhere we want in the Jungfrau Region, but only good for 3 days. Jungfraujoch is included in this. Shilthorn is excluded and would be full price. We would pay for individual tickets on the Switzerland leg of our journey to Rome.

Jungfrau Unlimited Railways Pass (235.00 per person)
6 Days unlimited travel. 50% off Jungfraujoch. I don't think there is a discount for Schilthorn. Similar to the Centenary Pass, we would pay for individual tickets on the Switzerland leg of our journey to Rome.

Swiss Half Fare Pass (110.00 per person)
I just recently found out about this pass, and my head was already spinning from the other 3. Are there exceptions for this pass, or is it exactly what it says: 1/2 fare on *everythng*? (Jungfraujoch, Schilthorn)

Based on what I've written, do any of these 4 passes jump out as being the best one? Or are they going to end up being pretty close in price? Some sites recommended combining (Swiss Saver Pass + Jungfrau Railways) but that seems like too much.

Another variable is that one of the youths will have a 3-Country EuroRail pass, with Switzerland being one of the countries. The cost for this EuroRail pass is not relevant as it has already been paid for.

thank you!