OMG, THANK YOU!!! I'm playing as Ariana in my main file, and it always bothered me how derpy her VS. sprite looked. It's like looking at Shulk in the original Xenoblade Chronicles vs. the definitive edition. It's a definite improvement from before. She's so much cuter than before.
Flora's sprite is also a giant thumbs up. I didn't feel that the old one matched her personality. Like, she's always sassing and bossing Florin out, but looked docile in the VS. sprite? Yeah, I wasn't really feeling it. And yeah, her head's humongous.
As for Aevis' sprite, eh, I like both of them, though the newer one would need getting used to. It just looks a little try-hard, and I kinda like the smidge of femininity in the original one. Though considering that he's supposed to be the unambiguously male character, I guess that would be not good. Oh well.
Also, I actually really liked Ren's old sprite probably because of his fox eyes, but I guess it doesn't really match his personality. I mean, he's not mischievous, but he was a Dark type-oriented trainer, so I dunno. Please don't change Ren's 2nd sprite! I really like that battle-hardened look conveyed in his expression. But what do I know? You're the artist, and it has all been great! Keep up the good work!
Edit: Actually, now that I'm looking at it again, I think Ren's newer sprite is suffering the same way as Arianna's original sprite. It has that same derpy feeling to it, though for Ren's newer sprite, it's easier to spot. His eyes are a little too far apart, so it feels out of place.