I hope to make it into backpacking as long as my dad did. Weekend recovery has starting becoming longer and longer so I think I'll be happy with half the years.
And yes, I found that 220 backs work with 120 film without issue regarding film plane and paper backing. I can squeeze 16 shots of 6*4.5 on a roll
and the 220 backs are about 1/3 the price of the 120s! As for the list, if you're interested in building your own, Lighterpack.com is a really great resource.
Here's my weekend full pack list. It really helps when doing a pack check to make sure you have everything. Great for building day pack lists too and we have one for the dog's pack so the saddlebag distribution is even.