As long as an upgrade pack for 1st edition owners is offered (just replacing the cards affected), then it would be ok. Otherwise, I think I'd be frustrated. Hopefully some lessons have been learned from the Puzzle Strike scenario...See I don't get the logic here...
I mean if you don't really play Yomi that much... maybe once a month or less, then the imbalances of the game won't be noticeable for you. I mean I only play Yomi... once a year maybe and I do not notice any balance issues.
But if you played the hell out of the game to notice these balance problems, it's likely that you got your moneys worth out of the game to justify buying a new copy of the second edition. And if you do, you have two copies of the game, one to lend out to friends or you could even play mirror matches. And imbalances can also be a good thing as well as you can handicap yourself by playing a weaker character against a new opponent.
So while I would like to own the second edition, I know that I haven't played the older version a lot and so it would be a luxury purchase if anything. As such, I'm okay with sticking with my first edition and hoping I can play the hell out of that.