The Giant Slayer node on the multishot tree is a really interesting node. I’m currently trying to make a multishot shotgun style build that utilizes it but that -80% more damage multiplier is pretty harsh. It’s not even fully counteracted with 3 points into the Point Blank node.
I understand the reason for the multiplier is most likely to limit the damage of ailment stacks applied by the skill since you can hit many many times.
I would suggest one the following options:
Make the multiplier on Giant Slayer -5% more damage per arrow with Multishot. (The max arrows you can obtain for multi-shot is 17 so it ends up being -85%, but with much less drawback on the earlier levels when that node affects you strongest.) You could reduce the stun chance to be per arrow as well.
Change the Heavy Arrows node to instead cut your arrows in half (rounded up) rather than limit them to 3. This would provide better synergy with the idea of “Multi-shot” and make the node much more viable for plenty of builds.
Provide any increases to base crit on the tree somewhere. In the past this was a much stronger skill to build around since we could achieve crit vulnerability of 100%, but with that change this skill desperately needs some source of base crit. Currently the best strategy is to use smoke bomb to increase bow crit chance limiting critical strike on this skill significantly.
Those are my ideas to make the skill a bit more rounded out, but it’s coming from some partial bias as I really like the Giant Slayer node but without already having near max arrow count it’s just better to run a different node setup or even different skill entirely.