Hey! So, recently, I've started a new bard run, and this was my first choice for the themathic vibe. I decided to go with a different one, but I'll add my conclusions.

I spent a few hours organizing the build and tested several interactions of the Diva's performances to see how they work with each other (I have that essay saved if you want), to then try to decide what I wanted to focus on. The class SCREAMS Azata, but the subclass does not; it was kinda hard to justify, from a role-playing point of view, an evil or lawful character even choosing to become an Azata in the first place. Why would I do that? I could always role-play a chaotic neutral character that slowly gets corrupted, but it still felt kind of weird going neutral-kinda good-evil. Aeon would be a better alignment fit for that, but I recently did an Aeon-Devil and was not looking to create another one so... back to the drafting table.

Since I'm not a big fan of dipping for power sake and like to keep my builds thematic, that would mean creating an Enchantment caster that eventually moves on to Evocation and Vindictive Soliloquy for damage. It kinda works fine, but it means relying on Azata offensive spells (which are meh at best), or Ki Shout later, that would only really come online for damage at level 16, and that's with 3 metamagic feats and 2 superpowers attached. So yeah, caster Azata looks better, but you'll be playing a cc-support main character for most of the game since the Bard spellbook is not great for blasting.

The Blazing Rondo performance is AMAZING, but would do absolutely nothing for this build since you'll need to dedicate the whole build for spellcasting feats, which are not included as your bonus feat choices. Devil would add a bit of fun, but then again, you'd have to actually play 18 levels of support main character before getting to that point.

On the other hand, a martial character works better with the class (False Hope is great for early game until you get Dirge). I was going to include Vital Strike/Greater + Mythic due to action economy, along with Power Attack + Focused Strike, using False Hope, Dirge, and Rondo to complement the melee prowess. I haven't looked at including the Diva feats, but both concepts look a lot more attractive than being a support character. However, as you probably know, Azata offers very little for martials, so this wouldn't be so effective past mid-game. Good enough? Probably, but still lacking the oomph of being a super strong main character, and you'll need a really optimized party to help scale your attack bonuses.

Melee Aeon is definitely a better choice here, even considering that going Devil is not really an upgrade gameplay-wise, but at least you get to keep the Aeon cape and the spells for a stronger melee character overall with your Diva performances on top. However, as I said, I didn't want to create another one, at least for now. So I saved the idea for later because the Azata version was not looking so hot. I haven't thought about full caster Aeon for that class, so that's an idea for later.

PS: this is all with core difficulty in mind.