Aldo wins. Barao is good, but I don't even see him beating a healthy Cruz at this point. Aldo has been consistently fighting top notch competition since 08.
That's...fairly crazy.
Barao would have been the favorite over a fully healthy Cruz. Just compare their Faber fights - Cruz and Faber had a good battle, Faber landed a number of hard shots on Cruz. Barao breezed through Faber and completely neutralized him.
Against injured, out 2 years Cruz, I'd be absolutely stunned if Cruz won that fight. And I'm pretty sure bookies would be stunned if Cruz won that fight too. Cruz isn't going to be what he used to be, and he probably wasn't as good as Barao anyway.
You could also use the Faber fights to compare Aldo and Barao actually. Aldo beat Faber so mercilessly that he actually took pity on him in the fifth. That was one of the most brutal one-sided 5 round beatings ever.
Barao totally shut Faber down and won easily, but Faber wasn't barely able to stand like after the Aldo fight.
Barao is good but Aldo is just better at everything IMO. They fight with a very similar style - perfect Muay Thai technique, combined with incredible TDD and explosiveness.
However Aldo is better than Barao at everything, except maybe cardio.
I mean if the fight is at 135 Barao probably wins because Aldo would kill himself with the weight cut and be gassed before the fight started. But at 145, I have a hard time seeing Barao beat Aldo who does everything Barao does great, but even better.