I like the low effort nature of the build, I don’t mind too much that it is slower (which I don’t deny) 
Yes, i confuse those a lot for some reason
The vine is supposed to leave patches on the ground which poison anything that walks over it. I’d agree that it’s behavior should be more predictable, but these patches should be reapplying poison.
Before the changes to wolves, I did do a build with max poison creeper and max rabies. It was honestly pretty good, albeit unpredictable as you say. My complaint is that you can’t really use it with the rest of the summons because it’s ONLY effective in hell with Rabies maxed, even with the massive buff to the skill itself. Frankly I think they should just remove that synergy and buff Creeper more, because th e synergy pretty much restricts you to using it as a companion to Werewolf builds.