Well from a visual standpoint she's pretty unique and not overly goofy so I think she'll be fine there. The ones who get strange and weird visual changes seem to be the more generic guys
Gangplank: went from a normal pirate to old pirate with a goddamn robot arm!
Warwick: went from a normal werewolf to a werewolf with a goddamn robot arm!
Sion: looked downright silly, was basically a reference character so they turned him into current Sion.
While the ones with more unique looks like Poppy and Ryze pretty much look the same just changed to match their new personalities. Because hammer yordle and blue guy with a giant scroll on his back are both already unique. So is blue girl with knives stupidly pointing at her inner thighs forcing her to walk like she's bow-legged. Though for what it's worth I hope they get rid of the inner thigh knives. She can keep the others around the outside of her legs if she really wants.
From a mechanical perspective Galio's theoretical core was area taunt, anti-magic, and ranged attacks. All of which were kept in a weird way. Some might say a more fair way, now that you can see the taunt coming. On that regard I'd expect the core mechanics of Eve to remain in some way: perma-invisibility and running around dealing damage. But they'll definitely be done differently. It's a rework after all.
From a personality perspective, anything goes. Riot likes to change things for the sake of changing them, sometimes. But I think we already have an Eve short story. So we already know her personality, roughly.