Sapper, wugushi and most likely cannoneer (and maybe QS and Rogue?) can be considered a High STR type and is recommended around 100-120 DEX, even less depending on equipment.
Musketeer has some skills with “X% + base damage” that benefits from STR builds. All Cannoneer skills (for now) are this way.
If you want to use Kneeling shot(can’t work with skills anymore) then going c2-3 archer is needed, and if you stops at sapper c2 like said above could be something like:
archer3>sapper2>rank 6?>Musketeer or archer2>sapper2>rank5>rank6>musketeer. Rogue, Scout and Falconer since they could help with damage and a hide, hit and run tactic maybe?
If you want to play with Quarrel Shooter, it’s necessary rank 3, because it’s when he really shines in my opinion. It would be QS3>Sapper2>Musketeer (you can go like QS>sapper1-2>QS too if you really want to play with earlier)
I can’t nothing about skills since there some chances of they getting a buff or nerf looking at what happened with some classes these days.