Ataides can still beat Aung, Karaki was cause Ataides wasn't available. And a 225-lb Vera may be too much for Aung at light-heavyweight.
If he can beat all of them and there aren't any good free agents available at middleweight (if ACB runs into problems with contract negotiations, Duraev would be a solid pick-up for ONE) by this time next year, they said they're expanding into Italy, so a one-night, four-man all-undefeated-Italians tournament to decide Aung's next title-challenger would be a pretty cool way to get him an interesting contender. Italians can be pretty big, so that'd even things out as far as random-athleticism goes. That could at least buy them some time until a good free agent pops up.
I predict ONE's gonna have Bigdash vs. Hasegawa for their Japan event next year, and Aung's fights with both of them were very close and highly entertaining, so that guy on a three-fight winning streak would be a very intriguing opponent.