As far as Cameron vs Maddox...both would be solid candidates.
Personally, I like track record. Daniel has sued Beshear every way he can and been one of the few voices in Kentucky doing actual work to oppose Beshear. He has an all-star legal team in the AG's office in a way that folks like Maddox don't have. It's one thing to say the right things, it's another to have the administrative capacity, network, and skills to actually do the right thing. He's taken Beshear's allies all the way to SCOTUS...and won. And won 8-1 at that.
He may not project the fire-breather image that someone like Maddox cultivates, but he's put in the work and proved himself in ways that many of his primary opponents have not (yes, I know legislators are limited in what they can actually accomplish). Bottom line, I don't think any thinking voter can write off Daniel Cameron as from the "establishment swamp." He makes friends in high places when he can, yes, like any good networker. But he's his own man.
This will be an interesting primary.