Pretty good game, would love to see how things change with updates. With that being said, I do have a few criticisms about some of the perks.
1. I don't really think the dragonfire potions really do much - with all perks purchased, each one does a whopping... 28 damage. I mean, it might be useful in the early game, but I didn't get to see that, given that I typically buy the cheapest stuff first, and the fury potion seems way better.
2. Hallowed Ground seems rather niche in its usefulness - the cleric tends to sit in the back, usually with only the bard near him, and they only ever get targeted when there's an aoe ability present. Could do better with the paladin, who's on the frontline.
3. And the award for "Most Useless Perk" goes to... Caltrops. Due to the way that enemy aggro works, they have NEVER stepped into range of the aoe, usually being intercepted in melee way before they can reach that spot, even with only the knight in the party.
Still, those being the only (and relatively trivial) issues I've noticed, this game seems to be very solid!