I was thinking this for my Concept, but I didn't know if it would sound cool or not.
Basically, as well as the DT gauge... I was thinking of having some fire arms have their own gauge too... After executing some moves from your fire arms, the gauge builds up. Once it is full, you can perform greater moves for a period of time with your fire arms. This would be like using two styles at once. Because you could be using Sword Master, but you would also be able to build up that gauge when you are using your fire arms. Basically, you can keep in Sword Master AND perform better moves with your guns, without having to switch to Gunslinger. In addition, if you are actually using Gunslinger and your fire arm gauge is full... Then the moves you get to perform then are some of the greatest moves you can do with fire arms in the entire game.
What do you think?