The weapons are not the greatest, no. It’s something I often find in these sorts of games, though. You don’t want the good weapons to be so far along in progression that you can’t use them much before the game ends, but you also don’t want great boomsticks handed out like candy early on, because that makes loot and rewards meaningless. Getting that balance right is really tough.
That’s above and beyond the issue of “feel” of the weapons, of course, which is probably what folks mean when they talk about how the weapons are a bit off, I’m guessing. I find that in most games the weapons most likely to feel good or “right” are the sniper rifles and shotguns, the ones most likely to feel off are the automatic weapons of any sort and pistols. FC 5 was pretty much no exception, for me.