High dex build ( 65-90 with Hyoyo ) :
XXX Str
30-40 Vit ( Varies on Equip + way to play )
66 Dex ( 66 + 7 from yoyo + 20 from cannon = 93 = Speedbreak )
15 Int ( Base )

Pure Str Build ( 90++ with Hyoyo )
XXX Str
15-30 Vit ( Varies on Equip + way to play // more Vita for PvP Build! )
15 Dex ( Base )
15 Int ( Base )

I would prefer high dex build until 95.
Crit is nice and you will got a nice hitrate as well.
But at 95 you should restat to bow because it makes more DMG and some other reasons.

Yoyo is mostly used for PvP because of Hop.