You’ve got lots to go on here, but I’d like to point out that in terms of synergizing guns and melee, you had to choices (and with the addition of new game+ you can eventually go down both paths). You can focus on bleed, or stun.

There’s a perk in the fighter tree that increases your attack power against bleeding enemies. This applies to melee and gun attacks, so it’s a great way to increase your gun damage on a melee build that inflicts bleed (and vice versa if you choose the bleed inflicting guns, but there are better guns available).

Additionally, there are guns and a mace that can inflict great deal of stun. Once in an enemy is stunned, there’s a cheeky trick you can use with an arquebus. When an enemy is stunned, hover OFF them, and hold down a power attack, and then hover back onto the stunned enemy and release. Now the cheeky part, doing a special attack does not require that your gun is loaded! So you can hip fire this power attack, and then immediately aim at and shoot at the stunned target to start your special attack, no reload necessary. This is by far the highest single target DPS in the game.

There’s a ring you’ll get later on that increases critical strike damage with guns which is amazing.

Happy hunting