(I didn’t put a lot of thought into this, just a random suggestion.) Counter break are not enough. I think combo breaking should cost a bar and they should remove air and juggle combo breaking. The two way interaction is nice and all but a lot of players don’t like the constant combo breaking. Or they could add longer lock out time when they combo break wrong.
Hopefully the KI team come up with a good ideas for season 3. I still like the game the way it is but hopefully they improve it.
You do understand that there wasn’t any air-based combo-breakers in S1, right? It’s what made Sadira so broken - they had to add the mechanic in specifically for her (she could combo you in the air all day with complete impunity). As for juggle-breaking, it’s only possible under specific circumstances.
Also, counter-breaks ARE enough - you just have to learn how to read your opponent more effectively. It’s as easy as seeing if they combo-break often, and at the same point in the combo. If so, then you can use a counter-breaker to dissuade them from doing it again. 
Using up (shadow) meter for combo-breakers is a really bad idea IMO, because it hampers the 2 way interaction that the game does superbly well AND would limit the other ways you can use it, such as with shadow moves and shadow-counters, both of which are far more useful overall. I’m sure there are other reasons why this is a bad idea too, but I’ll let others tell you what those reasons are. 
If combo breaking takes a bar, I might be able to kill your entire first health bar off two openings before you even get access to breaker. I would have to go to training mode to see just how fast you gain bar while getting hit, but it’s not very fast.
I would OS heavy auto-double after every opener and confirm into 50% unbreakable damage. On the off chance you had a bar to break, I wouldn’t care; I would let you break my heavy auto-double and spend the bar, then win neutral one more time and kill you.
If you don’t believe me that it’s a bad idea, you can actually test this theory by playing some casual matches with this rule in effect! Nobody is allowed to breaker unless he has a bar. When he has a bar and successfully breaks, take a small break from the action and force him to waste his bar with a whiffed shadow move. Play 10 games like this and let me know your findings.
Combo Breaking requires a Bar? Omen would be OP and Fulgore would be pathetic
Eh? Sadira being broken in S1 had nothing to do with her air juggles. She got a lot less off her juggles in S1 than she does in S2 - they blew up the KV meter insanely fast, and you couldn’t cash out any of the (minimal) damage you got from them. She got the safe counter breaker off the grounded juggle, but in general you lost your setup for trying it, and since she got so little off the juggles there wasn’t much reason to break them anyway. For all her air mobility, Sadira’s air juggles in S1 weren’t particularly special or fancy.
Sadira’s brokenness came from her cheating the opener system with jump cancels and looping repeated opener blade demons; that capability wasn’t really tied at all to her air juggling capabilities.
With respect to the OP, meter required for breaking is a bad idea - @Infilament gave a pretty good rundown for why. Combo breaking is also a lot less immutable than many people seem to think - the game already provides a lot of ways to get around and punish the attempt.
It’s probably time to set up a master thread on the combo break mechanic. This is about the third different thread on the subject so it would be good to keep this all tied up in one place.
I think people recognize that it is frustrating to get broken. It’s frustrating for me. But it is a fundamental for KI. If the other guy is better than you at breaking combos and tricking you into lockouts or comb breaks, then he is simply better than you and deserves the win. That’s the game. Personally, I don’t think the game suffers from too many breaks.
You pretty much just described MKX, but with no execution barrier for large combos.
Heh, it’s kinda true. Although I think in MKX you need particular starters to get your big damage? Not every character can start the big string off both an overhead and a low (the lucky few can), and not every single poke they ever land will lead to 50%.
That’s the big thing about KI; every single hit you ever land can and will lead to big damage if the other guy doesn’t break it. Could be full screen wind kick, a fast overhead from 3 character lengths away, an amazing space control normal, a low short, a jumping attack… doesn’t matter. Only exception that comes to mind is, like… Thunder command grab, but you get the unDPable vortex after it which does lead to the above, so yeah.
To be fair, you need to guess confirm many of these things into an opener to get that combo, which may mean risking giving up frame advantage or opening yourself up to shadow counters, or may just not be the main priority for throwing that button out there in the first place.
Yeah, fair, with the current KI ecosystem this is true. Some buttons just aren’t canceled into specials because you’d rather have the space control and not the up-close disadvantage.
But if the combo system was changed so you needed a bar to break, I think suddenly the possibility of your poke becoming 50% guaranteed damage would change how you approach the neutral and you would probably start canceling into openers a whole lot more. A change to the combo engine has tons of implications across all facets of the game (neutral, oki, etc) so real care has to be taken when changing any one piece.
(Also you suggest shadow counter as a thing, which is true now for sure, but would the relative value of shadow counters be the same if that 1 bar you were saving is needed to avoid 50% damage the next time you get hit? Also, would you even have bar that often? You’d probably have to spend it immediately every time you get hit so you don’t immediately die, so you probably don’t have it in neutral that much. I think they probably wouldn’t be used that much in this theoretical version of the game)