You might look at the 2-month continuous Eurail Pass, which is on sale right now (25% off). This would be $1375 for 2 people (regular price over $1700), and you wouldn’t need a Swiss Pass. . I usually do not suggest using a Eurail pass in Switzerland, but I have seen others confirm that they do work well, with a few exceptions (which I hope someone can explain to you, as I can’t).
https://www.ricksteves.com/travel-tips/transportation/trains/global-pass
Note that neither a Eurail Pass nor a Swiss Pass will fully cover the high mountain lifts and trains (cogwheel trains, cablecars, gondolas) beyond the villages. Most are covered at 50%; the Jungfrau train is only 25%. But I wouldn’t recommend that for someone on a really tight budget anyway.
If you do intend to ride those fun and scenic lifts in the Berner Oberland, you can do that for free with a Berner Oberland Pass. This covers all trains, boats, buses, and (most) scenic lifts within a broad area—-From Bern or Luzern down to Domodossola in Italy. Lifts excluded from the full discount are the Jungfrau train and the First lift at Grindelwald (0robably became too crowded).
This will cost 435 per person for a 10-day consecutive pass. Or you could each buy a Half Fare Card for 120 CHF and the Berner Oberland pass will cost 316 CHF. In other words, the Half Fare Card cost is covered by the reduction in price for the pass. Then you use the Half Fare Card discount for the remainder of your travel throughout Switzerland.
https://www.berneseoberlandpass.ch/maps-bernese-oberland/
See the 2025 prices and map of validity here:
https://www.berneseoberlandpass.ch/assets/Uploads/Berner-Oberland-Pass-Prospekt-2025.pdf
Combine this with a Eurail Pass of appropriate length to cover your travel in the rest of Europe—-maybe a one-month continuous pass, or a 22-day Flex Pass if that works better.
That brings the cost per day for riding trains, boats, and lifts in Switzerland to 41 CHF. If you look at the actual prices, you will see that one simple lift ride can cost more than that. For example to ride up the popular Männlichen cablecar, walk the scenic Panorama Trail to Kleine Scheidegg, and ride the little train back down to Wengen would cost 60 CHF each. A regular train ticket from Bern to Wengen is 45 CHF (reduced to 33-39 CHF if there are SuperSaver tickets available, but these sell out in summer).
When you check train prices on the Swiss train site, the default selection is with a Half Fare Card, so you have to either disable that or double the price you see to get the regular price.