This build sounds quite solid (though i’d take some points off stone picking/shot and get a higher level pavise, which’s super useful for getting mobs attention and save your fragile arse). Wugu’s skills are pretty much what you’d expect really.
Stat-wise, you’re likely better off dropping all that dex though. Without kneeling shot, even your running shot would benefit much more from STR as it is, and since poisons can’t crit, going higher STR would be a win-win pretty much.
For Rank 7 you could either go with Musk for extra super burst on running shot down time (blow+wugong+gu pot+snipe+headshot+covering fire would pretty much increase single target damage by a whole lot).
Or simply try to compensate for your lack of AoE by going cannoneer.