The things that pop out to me is that you need the Firearms Training talent before Grit talent, regardless of whether you have proficiency or not. It can be useful if you go Pistolero or Musket Master to get full proficiency, though. Extra Rogue Talent picked up at the same level will zoom you straight there. Also, you have a free deed from Amateur Gunslinger, which I'd suggest you choose Quick Clear or Up Close and Deadly.
As for your extra talents and feats, since you're going Deft Shootist anyways, I'd suggest pursuing Snap Shot, Combat Reflexes and Precise Shot, the last since you're going to be dealing with that melee penalty quite a bit. Combat Trick and shoving around your Fighter levels can help you get there, as well as potentially replacing Quick Draw, as TWF makes it so you can draw both guns as one move action or as part of a move. The Snap Shot talent can also be very beneficial to you.
Snap Shot and Combat Reflexes are definite wants for a Gun/Monk. Also, call the build John Preston.![]()