You can level your weapons however you want to, I don't believe there is a right or wrong way.
But you should remember that when a weapon reaches level 25 (Mastered), you will NOT get any more Rep points towards your Notoriety. Which means if you want to reach Pirate Master (Notoriety Level 40), you will have to use other weapons to get those Rep points. You also get Notoriety (Rep) points doing the Pearl Quest (and Weapon Quests), but that alone is not enough to get you to Pirate Master.
So what I was trying to convey above was BEFORE I knew about the NOT getting any Rep points after a weapon was Mastered, I favored my Voodoo Doll and got it to level 24. (And because I didn't like the Grenades, I didn't plan to do anything with them but changed my mind.) AFTER I learned about the Weapon (Rep) Mastered situation, then I started working on all my weapons equally (keeping all my weapons at the same level, well except my Voodoo Doll which I had already leveled high lol).
It's a lesson I learned almost too late, so I was trying to share what I learned with others.
I kept mine equal because it was easier for me to rotate through the weapons (usually a level at a time), and not have to suffer having to do several levels later on (although that's exactly what happened with my Grenades lol, I had to suffer several levels of training to catch up to my other weapons, again trying to pass on a lesson learned lol).
So as you can see everyone has a different approach to leveling their weapons, and it appears we're still reaching Pirate Master lol.
Good Luck, and have fun!
