Please critique my build (DW Fire Purifier)

First time I’ve dabbled in a Pistols-based build. Please criticise and let me know of any obvious mistakes.

first, it’s basically impossible to proper comment on a build without items, because they add so much, not just in terms of base stats/resists, but also skill points that make potential break points shift

right now the glaring thing is you took both Revenant and Elemental Crown devotions, since they both do flat RR they don’t stack, so it’s kinda wasted to take both in that regard
not taking brimstone on a ranged/gunner is basically criminal, imo
couple of potentially over-invested skills, hard to tell without gear, and a bunch of under-invested too