Yeah you think you have the best weapons but there's also signature weapons which you only get by collecting letters and relics.
While there are better weapons, they aren't required and a couple of the ones I had were massively overpowered, like insanely so.
What games tend to for progession is start you off with a toddlers gun, then work you through up to a real gun, then really good guns. IE taking on a massively military complex with a peashooter is bad, but you work your way up, get a decent weapon and it makes a full scale attack doable.
FC3 lets you get very good guns that are basically better than anything any enemy has, within what, an hour of starting the game even playing normally, less if you went straight after money, AND also being able to smack a silencer/scope to take out entire camps from well out of danger.
It really should have been worked far far better, with increasingly difficult camps to take over, with more people, better defenses etc. Instead it was easy start to finish, with great guns start to finish, and any feel of danger lacking from the very start.