Link: spin attack op. I'm guessing it'll become less relevant postgame but the Master Sword having 300 atk while all my other weapons are like mid 100s tops made him pretty nuts in comparison to other characters.
Zelda: Didn't even get to play her again after the prologue so I don't know how she plays with upgrades lol
Impa: Bleh. Feels clunky. Maybe things changed with upgrades but I didn't really want to give her another chance, she got dropped as soon as I was able.
Sheik: Pretty alright. Serenade of Water makes me feel she's designed for longevity, but from what I've played so far I'd rather have raw power in every situation and she doesn't seem to stand out in that regard.
Lana: Really fun. Feels like she has tools for every situation, and I love the versatility to her blocks in being able to dash into them for explosions. Dodge cancel dashes are also amazing both for chasing after attacks as well as general movement.
Linkle: Also really fun. Terrific crowd control (R5 is a 180° arrow spray that pulls everything directly in front of you, range is dumb), really silly Strong Attack that builds lots of damage/meter and launches+links into normals (bosses don't get to do anything), and some really damaging combo moves. Also adorable and bad at reading maps.
Darunia: I played him for like 30 seconds once to give Zelda a potion
Midna: Also haven't played enough to give an opinion of.
Fi: Wished her R2-R4 linked more quickly, I like playing her for the most part but she feels lacking when it comes to smashing weak point gauges that disappear quickly. Nice flow to her moveset otherwise, juggles decently and has an amazing dodge.
Ganondorf: Slow. Running around as longhairdorf with two greatswords feels so right, but...SLOW.
Zant (didn't unlock from story, how2get): Experimented with a bit during Ganondorf's story segment. Somehow both unconventional and quirky yet incredibly boring. C2>spin>special>repeat. Seems pretty efficient but...ugh.
Ghirahim (didn't unlock from story, how2get): Quick launcher+quick combos for smashing weak point gauges more reliably than Ganon/Zant, projectile normals were a nice bonus. Ended up favoring him for Ganondorf's story missions despite not being able to unlock anything for him. Bonus points for insulting Linkle's fashion sense and wanting to capture areas for their aesthetic appeal.
Cia: Fast+large normals, decent combo moves with situational but well-defined uses. Satisfying special. Her laugh gives me strength.
Volga: Pretty straightforward, disappointed that dragon form didn't get more use than just "float in the air for a bit then crash" but his combination of range/speed/power is pretty silly.
Wizzro: Haven't gotten to use much yet, moveset seems decent but I didn't find him very fun. Bonus points for amusing dialogue.
Twili Midna (playable for only one mission cri): CANNON

: Lana, Linkle
A: Cia, Volga, Twili Midna
B: Link, Fi
C: Sheik, Ghirahim
D: Zant, Ganondorf
E: Impa
More playtime needed (will probably like): Midna, Zelda
More playtime needed (will probably dislike): Wizzro, Darunia