Interesting! The original Bolt Ace did have some holes in it, and this patches them nicely! I like how Sharp Shoot is nerfed to only the first range increment (not really a problem with crossbows, since that's at least 80 ft.), especially once Signature Deed becomes available.
The one thing I'd personally change: Move Crossbow Training up a few levels. Getting Dex to damage on a ranged weapon is insanely rare; to my knowledge, only the Gunslinger gets access to that. The relative lack of damage bonuses on ranged weapons is what balances them against melee weapons, since archers have to constantly choose between Dex for accuracy and Str for damage. On melee weapons, I have less of a problem with easy Dex to damage (like Unchained Rogue, or even just putting it in Weapon Finesse), but ranged weapons already have the benefit of being ranged.
Put it this way: A one-level dip for Dex to damage with any one crossbow? Any Ranger, Hunter, or even Alchemist build I make would almost automatically go for that, and I don't like level-dipping. The regular Gunslinger and Bolt Ace both get it all the way up at 5th level for a reason.