Currently, in our iteration, Poison Vial is neither a generator or a finisher, which is my biggest gripe with it. The Rogue's resources are there to be used, but we're not using them. This is an indication that there's a mechanical issue somewhere (Envenom perk). We could try fixing Envenom, but could it rather work if Poison Vial was changed to a generator costing ~30 Energy and granting 1 CP? There would still be burst potential if you pool ~120 Energy, it wouldn't require Envenom to be up, and it would build CPs towards Envenom/Rupture.
Another gripe is that throwing a vial in melee range doesn't make sense realistically. It could be ground-targeted, but I really despise ground-targeted AoE. It doesn't cohere well with a melee class who's typically running around a lot (using the mouse) to move the cursor over to locations. Especially when our iteration of Poison Vial is looking to be used in rapid succession.