Andor's Trail

Of course, I think Investment should be rewarded instead of punished. More you have to invest, better reward there should be, no?

Yes, but not that much. It would make you almost invincible. If I have 4 attacks per round and land all four hits (quite possible with a high AC) I would get back 28-32 HP, even at only 1% of AD.

At endgame without any other items its basically 4-6 HP per hit. Thats basicalls dual wielding RoLs+RoLS. Is that really 2 much? I think taking no damage is better payoff than a bit of lifesteal while having to invest every skill point into making it work..

Sorry. I'm calculating 10%, not 1%.
But that brings up another problem. All numbers in AT are rounded down to the nearest integer. So if you did 99 damage, 1% of that is 0.99, which rounds down to 0. You get nothing. Even 3% may get you nothing unless you can deal a large amount of damage per hit. Possible of course, but biased towards high attack cost weapons with a high DM. So it might actually work

Yes, you are most likely dealing 20-60 dmg by the time your build starts looking like smth, so somewhere around lvl 50ish. I am calculating 5% which will end up being 1-3 HP per hit. Which will end up being 4-6 HP per hit, counting Vampiric Touch 3. It will scale up to 3-5 HP per hit by lvl 100 i assume, counting all yet to be added items. I think thats fair and decent enough.

How about instead of the skill being there at the choices why not try make it so that you can avail the skill through a quest and since there are oegyth crystals, make it so that collecting 10 or more to be able to learn it, since it is OP, it will be balanced by not being able to take certain quests and suffer some kind of abnormal status when consuming certain stuff, if, and only if, you have the skill?