Some items give you a strength boost for a few minutes which increases your carrying capacity so maybe that's why you can sometimes carry more than usual.
Either find a gun that is the same (model) as the one your using and use the weaker one to repair the one in better condition when needed, (Do not use weapons that are one of a kind to repair normal ones because you will never get them back) or find a NPC that can repair it for you usually in a store.
I love Jury Rigging. As to what stats are useful it depends on how you play. If you use guns a lot, then obviously the guns stat is important. Sneak if you like to be stealthy. Lockpick if you like looking through all kinds of containers. Speech if you wanna get an advantage in certain situations.
just got the game two days ago, been playing ever since. im at the correctional facility, disguised as one of these power dudes. doing a mission for eddie, but i read online i should kill all of these prison guards?