Best Grill?

Grill? What do you mean? I don't see you cooking any meat on that thing. >:(

I mean, the only way I can see this getting better is with Wrath, but not everyone has that kinda fodder at their fingertips

Quick Riposte can work better alongside DC, but Vantage is also good.
Just wish I had the Soliels needed for that.

So your grill can also smoke meat, awesome! Looks good to me, like said Wrath would be great B skill if you manage fodder.

The best grill is charcoal for that deliciously smokey flavor, but since Soleil here seems to be capable of smoking your meat(get your head out of your pants) I'd say she can qualify. It's a good set, though with her atk, she might benefit from Heavy Blade seal instead.

Desperation?

Extremely strong! Other B slot ideas would be QR to guarantee a double or better yet Wrath to absolutely annihilate with Glimmer as if she were Ayra