Basically, title. What is the actual consesus for a Hackapell build? Ranger3, Qs3, Rogue 3…etc?
my alt Hakapalle is A1-R3-F3 magic arrow stacks very well.
depends on what you want to do. QS3 for single target. Ranger3 for mobbing (easier to stack arrows with Barrage) Rogue3 you can only use BS and Sneak hit while mounted. other skills will dismount you (even feint or lachry or vendetta which makes no sense at all)
How do you think your hacka build will compare to mergen as far as bossing?
Well tbh, I prefered Mergen over Hakapalle for WB because of the range advantage (and play style). It isn’t gear as much as Mergen and lower attributes 
so I can’t really make a fair comparison atm.