All of the Minolta A mount, Konica Minolta A mount and I believe with the 70, which is the last generation of Konica Minolta film cameras will work with SSM lenes including Sony A mount lens. You might need to check the manual on SSM lens. In terms of primes, the Minolta 24, 28 and 35 are very good primes. For hiking, fast film, such as Tmax 400 pushed to 800 I would think about the 24 to 80 F 4.5 or the 28 to 135 F4 to 4.5, both are heavy but will do the work of 3 or 4 lens. My examples are sharp at F8 to 16, on my Minolta 9 or 7, AF is fast. If your 70 works with SSM lens, the Sony 28 and 50 are not too expenesive and have updated coating. I have a couple of 28 to 200s, Sigma and Tamron in A mount, dont like any of them very much. In terms of light weight and good coverage just slower is the 28 to 100 4.5 to 5.6 D lens. A good bargain lens is the 35 to 70 F4. I have a number of bags, all very old, doubt any are in production. For hiking I use a sling backback that takes body and 4 lens, room for 10 or so rolls of film along with a filter wallet. If you stick with a 28 2.8, 50 1,7 all you need is 49mm filters. Once you go fast such as the 28 2.0 or 50 1.4 you need 55mm filtes. My standard hiking kit is a 28, 50 and 100, along with one longer zoom like a 70 to 300 4.5 to 5.6 APO. D. it is light enough and does not add much weight but provides longer reach if I run across any wildlife. If you 70 works with SSM lens and you have deep pockets and want the best then Sony Ziess in A mount are really sharp lens.