Life leech. Always a controversial topic in Diablo 2. I recall it with equal parts fondness and disgust; at its best, it was a tremendous feeling to blast through a dense pack of baddies with nigh invulnerability, sucking life back so quickly that even massive amounts of incoming damage were trivialized. At its worst, it was a game-killer, as you found yourself stuck against a group you couldn't leech from for whatever reason but who didn't stop sending massive damage your way.
This recollection was really only relevant in the end game. Not that it wasn't valuable in the beginning of the game, but the fact of the matter was that for most characters its role didn't have much significance at all because the gear just wasn't there to support it. Even if you could find leech gear, it usually was in amounts scarce enough to be negligible.
And that's the nature of percentage-based life leech. It's impossible to balance. In virtually every game out there that involves equipment-based character progression, damage *always* increases significantly faster than survivability. Not typically a problem in a PvE scenario, because monsters can always be adjusted to fit. But... that changes when you've established a system of linearly converting damage into life. Suddenly, that exponentially increasing damage output translates into exponentially increasing survivability. Naturally, since the game designer wants to provide a challenge, they're forced to up the incoming damage to compensate. End result: Incoming damage so huge and spikey that you're screwed the moment you stop dishing out damage for whatever reason (examples from Diablo 2: unleechable skeletons, Iron Maiden, ranged attackers that you can't reach in time).
For all intents and purposes, it seems like Blizzard is intent on not only retaining life leech mechanics in Diablo 3, but extending it to all damage for all classes. In my estimation, this is a huge mistake.
I really like the way things are shaping up in the beta right now. The limitations on health potions mean that you've got to manage your health carefully and intelligently, avoiding getting surrounded by too many damage-healers, potentially having to evade attack for awhile to re-stock on life. It adds an almost cerebral quality to a game that's already fantastically action-oriented. Strong tactical elements in a game with great control precision and twitch-based gameplay? Magic!
We should all be legitimately concerned that this system is going to degenerate into another life-leech-centric scheme, where one-shot kills are the only way Blizzard has to deal with the fact that you can heal practically instantly the moment you start doing damage.
That said, I am *not* opposed to the idea of mods that add a fixed amount of life when you hit an enemy. I think that's fairly manageable. If you know how much life a character has at any given level, then you can pretty easily figure out what a reasonable amount of fixed life-regeneration frequency to balance around. This, I think, is a very different beast than percentage-based life leech, which ties your healing to your damage in a way that's frankly just impossible to balance.
I have to assume that Blizzard is figuring this out as they playtest the final stages of the game in the lead-up to release.
What are your thoughts on this problem?