Crossbows are actually very strong, they just get a bit frustrating in the late game when you meet a lot of armored enemies/robots, as you need to craft a ton of elemental bolts.
Though I have a few suggestions how to improve this:
Snipe is a bit of a gimmick, much better to take Sharpshooter
Quck tinkering .. yea might save your life but I rather take Hit and run, it negates all move and shoot penalty for xbows so you can now utilize corners better
4 Str/4 Will is useless, Better to invest into perception or agi
5 Con ... well you will always be squishy. I think you would be fine even with 3/4 con. But here its more about personal preference