With decent gear the reaver is amazing. Heal on kill would be a cool addition as I could use some different rings and it would really help newer players. If you are new...Reaver gets much better. Just keep playing and get some gear. We all started out garbage too.
My Reaver:
As I posted above I'm at 52.92% heal on kill. As such, I only use Dragon Rage as my main attack. It's mapped to my right bumper and I just hold it down for maximum MAYHEM. I don't even care about the health I lose from the power as I murder fast enough for it to not matter.
Other abilities...
Mighty Blow: I use this to deal with pesky blockers and especially the shield guys. This will also heal you with rampage, so that's a bonus.
Rampage: Bonus attack speed? Yes please. Damage bonus...also awesome. You can switch to a regular attack for some healing; helpful vs dragon. Dragon Rage used to grant health with this. It no longer does. You just do not lose health while using DR. This is fine for me...I would prefer it this way. I am worried that if it is changed back, the bonuses will go down from 20% back to 10%. I activate this as often as it is available.
War Horn: This is also useful for folks who are blocking you. They stop that nonsense and run...so you can kill them. Free crits is amazing...this speeds up cooldowns, so you can't go wrong. The upgrade deals 1200% damage to guard, which is huge when fighting the dragon.
Sure, you may catch a stray arrow and go down...or a mate may steal a kill that you needed...but overall, this is one of the most fun classes to play.
Also, I don't think devour can be blocked. So that is another option...this is why I love fighting demons; they don't block. I don't use devour as I am usually at high/full health and it would only do 100% damage. DR does 200%.
How about letting Dragon Rage deflect arrows like the spirit blade? Now that would be a nice bonus...
Maybe while Rampage is active get a reduction in projectile damage...or all damage?