(and maybe bombs?)
Okay, so something that has been bothering me is how much the game encourages use of guns. Guns are just better. They are much less risky to use, and make your enemies just as dead. For the most part enemies aren't good at avoiding your shots.
Pretty much whenever there is a dangerous situation, it's better to keep your distance and shoot at it. Or better yet, heard the enemies behind a half wall so you can shoot them without worrying about their projectiles hitting you.
So what is your motivation to use a sword? Time. You are able to kill things quicker. There's no time limit though, so your best encouragement to use them is being bored shooting guns. That's not very awesome.
Basic risk vs reward tells us that swords should give bigger rewards because they're riskier to use. Giving swords a power boost or guns a power nerf will not change that saving time is your encouragement to use a sword, and will not solve the problem. You could make guns harder to use, but that will likely just be frustrating.
A possible solution I see, is to make it so enemies killed with swords are more likely to drop better items.
I think that would feel more like an artificial solution. If swords, guns, or bombs are overpowered or underpowered, they just need to be rebalanced.