On the subject of whether guns do more damage or not, it's more that the issue, fundamentally, is simply that swords just do the job better than guns due to their speed, versatility, and power, and a damage bump isn't going to change that. How about we add the option to make guns better through an equippable with the caveat that it also makes swords less powerful?
Steady Shot Focus Module:
+30% damage for Guns
+30% reload speed for Guns
-60% attack speed for Swords
This would make guns a more appealing option for players who like guns, while at the same time make swords less useful and maybe even a hindrance for people who equip this focus module.
The only way to balance guns is to give Gun-users the same opportunity to get damaged as sword users. It's a risk/reward thing. If you can hit an enemy while nowhere near them, you could be doing one damage per shot and still have an advantage over a sword user doing 500 damage per attack.
That's why I, personally, suggest that an item of this nature that modifies a gun's attack speed and reload speed should take up the Shield slot. It shouldn't necessarily completely replace the shield, but the shield shouldn't be much stronger than maybe a proto shield.
If you buff guns, you have to also nerf the player's defense, movement, or health in a way that balances them with sword players.