So I tried the Top CDR Spell Vamp Tank Karma out and didn't go so well. Could be because I was against a Ekko and he's ridiculously strong right now, but even during the Mid/Late game I didn't really have the damage to be even remotely a threat in team fights, and even with decent HP and defensive stats I was still getting destroyed in seconds. Though I do feel Spell Vamp is still good on Karma, but I don't know if going all out with Spell Vamp Runes/Masteries, with Wota and Spirit Visage was the right way. Maybe just getting a Wota as a 2nd or 3rd item on pure AP Karma would probably be more effective.
However, I did do another game right after going Pure AP. I was using normal 21/9/0 masteries with a 36 Ability Power rune page so with D-Ring I had 61 Ability power at level 1. Although I was only up against a Nasus which is generally easy to bully with range...I still ended the game 10/0 and was still destroying people with what damage she has left lol.
So after playing her a few times, I do like the changes on her. In most cases you don't often use Mantra W for the damage, so losing that damage probably wasn't to bad and I love the fact that you can hit monsters with it. During my game, there was a time when the Nasus jumped on me and used both his Ignite and Ult and got me down to like 100 hp left...So I just stepped back and Mantra W'd the golems in the jungle (I was red side ofc) giving me about half my HP back and was able to stay in lane and defend tower.
And now with the increased root duration, when your jungler comes in for a gank...Just make sure you smack them with your Mantra W which by the time you hit level 11 I think the duration is around 2.25 seconds on the root (of course the 3.25 when your level 16).
tl;dr: I like the changes to her and of course she got a massive buff as a support, and I feel that she's also better as a top lane mage. AP Top Bruiser might still be a thing, but probably in a certain build. Though I don't know if she is still a good Mid laner since she did lose some burst and that's generally what Mid lane is about.