This suggestion pairs with my other suggestion about IFVs, and I'll be using similar arguments for both. Don't discredit this suggestion just because it's a PvPer complaining about non-PvP stuff. I really only play ccnet and find most PvP servers boring. I like the custom features like movecraft, but I think they can be improved.
*I will be using the word PvPer to refer to players who fight on the battlefield as infantry*
Guns have always been a little shaky in terms of balancing. Either they are too weak or they are too strong, but they are a completely custom feature, so it's only natural that things aren't balanced without a lot of testing and change. My main issue with guns right now are the players hiding in claims shooting at the PvPers fighting at banner. Why should a player hiding from the real battle be completely safe, while also doing more damage than PvPers? Guns can do up to 6 hearts (that was max I saw at the most recent siege), while a netherite sword does 2 hearts max. Players shouldn't be able to deal this much damage while being completely safe in a small box in a siege town or on their fort. It's a very low risk, high reward situation. The only way to stop these players is if PvPers get on top of the fort, which is extremely easy to prevent. Even if PvPers get on top of the fort, the gun players can easily walk a few blocks forward and be safe in their gank. If a player wants to participate in a siege, and they want to fight (shooting counts as fighting), then they should face the risks just like everyone else.
My only solution to fixing this is to prevent guns from being used in claims while in a siege zone, or reduce the damage done while in claims in a siege zone. This will require the players to at least be out on the ground where it's more dangerous, but that's the most fair option. The players can still be near the ganks in case they get into any trouble, and it's not like they don't already come down whenever it's time to cap banner. I don't see how this is unfair at all, and is definitely a more fun mechanic for both sides. Sieges are meant to be exciting and thrilling, so I can't imagine hiding in a safe box being much fun.