Catherine seems strong, but the right amount of strong.
I haven’t noticed a difference with Inara. The extra damage is certainly welcome, but she still usually doesn’t kill on her own. She never had a problem with her ability damage, her weakness as a damage dealer has always been that after her A+B she doesn’t do anything significant. That hasn’t changed. She’s always been useful in spite of not being a good killer, and that hasn’t changed either.
Caine is a bit less oppressive, but I don’t think he’s fixed. The ranged execute mechanic is just a bad idea. It’s just too effective in team fights.
I’ve only seen a bit of Warhawk; so far he’s not impressive. His Ult is wicked, but I’ve only seen him built CP, and he seems to take too long between abilities for his CP to do significant damage. It might be a matter of people learning him, and I’ve only seen him in a few matches.
The Alpha buff doesn’t really address her problem in 5v5. In 3v3 she might be better, but relying on healing to survive in melee in 5v5 is like eating soup with a fork.