The fact that all those skill bonuses are additive is horribly shortsighted on the part of the blizzard devs. Any other damage increases in that category (which is the vast majority of damage increases) are going to be totally useless. Power Pylons are going to be barely noticeable, for example.
I mean, I can see why they're doing this. They can't afford the QA overhead to rebalance the core skills until the next expansion, I suspect because they don't want to mess with the leveling experience. Adding items lets them buff the skills without having to worry about the pre-70 experience. I hope they figure out a better way to buff skills that need it.
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If you're using lifesteal, then the proc coefficient doesn't matter at all. The only thing that matters is how much damage you do. If bounding light deals more damage, then it'll be better for lifesteal. This is true of all runes of FoT and of all skills in general; lifesteal ONLY cares about your actual damage output, so anything that hits hard will generate a lot of life.
Since Sweeping Wind: Cyclone is powered by chance on crit, you will get noticeably more cyclones out of FoT:TC than any other FoT rune (and in fact no other spirit generator produces as many cyclones). This also powers your lifesteal if you have high crit chance, because SW:C scales extremely well.
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OP: LoH is a way to get health back that scales with attack speed, which used to be amazing. It's also only found on rings, ammies, and weapons, which means a single item can have a LOT, so a few pieces of gear can dramatically improve your life regen.
Also, it scales with the number of things attacking you, which nothing else does. It also is even better than it sounds because skills taht hit twice often give most of your LoH on each hit (Fists of THunder:Thunderclap is like this, 150% LoH on the first two hits even for just one target because of the cleave).
Try grabbing a blue amulet with 500+ Life on Hit and see how mcuh of a difference you think it makes.
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FoT:TC has mediocre 75% coefficient but it procs off the cleave AND the punch, giving it an effective 375% coefficient over the 3 hit combo.
WotHF has a lousy coefficient unless you use the run that makes it apply holy damage over time. That rune gives you a 370% coefficient, but WotHF doesn't attack as fast as FoT, so you get less life per unit time. Plus, that rune isn't very good when you're maximizing attack speed, since dots are based on weapon damage range, not dps.