Just a short input in between.
It occurs to me, that balancing is one of the evergreen issues.
My idea, which definately would need some elaboration, is inspired by the way tabletop or pen&papers handle the issue:
The player gets a point/score system which they have to manage.
Weapons and equipement have, based on their specific power, a point cost. So you can take the OP-weapon, but have to take the disadvantage of a crappy weapon in the other slot …
I think this could be a feasable way to get underused weapons and overused weapons in line!