Fun fact: "Medli" is actually spelled "Medoly" in other languages as a spin on "Melody".
Medli means a lot to me, since she's the center of my favorite part in the Wind Waker: the Earth Temple. She's just so adorable and I enjoy the team-up action between her and Link. I'm always sad to let her go at the end of the temple and of all the controllable characters other than Link throughout the Zelda series, she's certainly my favorite.
Therefore I was quite happy about the announcement that she's finally going to be playable again, as part of the Hyrule Warriors roster. But the outcome doesn't make me as happy. Like the other Wind Waker characters she's somewhat underwhelming and she sounds more squeaky than she used to, even though they apparently got her old voice actress back (Chiaki Takahashi). It's not as bad as Tetra, but it could have been better.
Anyway, her moveset is alright, but certainly not outstanding. I'm not a fan of tornado moves and she has two of them, her C5 and near the end of the attack string. The latter gets followed by a beam of light and while it seems like a good combination (the enemies inside the tornado get illuminated), I wish that the beam move was somewhat more accessible, because I enjoy using them with characters like Skull Kid and Wizzro. The Lyra was used like a Mirror Shield most of the time in The Wind Waker, so that functionality should have been a little bit more prominent. Her C3 seems quite useless to me and I would trade that without a second thought for more light beam action.
She also got a unique mechanic, where you can fill a bar with her Strong Attack or her C6 and then attack in the air with dodging during certain combos. It's somewhat similar to Tingle's Strong Attack mechanic, but different in execution, because you actually attack using the dodge button. However, to my experience this only seems to work with her C2 and C4.
Quite some of her attacks end with getting dizzy or clumsily dropping on the ground, which makes her even more adorable, but it's also an issue with her safety. She seems to be a very unsafe character. Especially her glorious C6 leaves her open for attacks, which takes away quite a lot potential. Some more dodge cancels and invincibility frames would make her a lot better. She also doesn't seem to do well against Giant Bosses. The C6 does take a way a good amount of the Weak Point Gauge, but it's not enough and you might have to throw in a Special to break the gauge in one go.
I do like, how she flies over the battlefield as her running animation. That looks really great and I had something similar in mind for Marin, who could transform into a seagull to fly around. But even if she doesn't, Medli gives me already my dose of fly-running.
I also like the design of the third tier of her weapon. It looks absolutely amazing and is certainly one of the best looking weapons in the game. Great job there. The fact that she actually uses a "Rito Harp" as the weapon type next to Sheik's Harp also opens some doors. For example a Hilda really could get a "Triforce Scepter" next to Cia's Scepter or a potential Nabooru could get "Gerudo Scimitars" next to Zant's Scimitars.
If Medli gever ets a second weapon type, I suppose the Grappling Hook would be the best fit, since it's a tool of the Rito and Medli originally gave it to Link. So, maybe that won't be Toon Link's weapon in the DLC, but something else, e.g. something with Phantoms. We'll see. Toon Link has more than enough possibilities for additional weapons and I hope that he won't take away from other characters.
Material-wise Medli seems to be a Ganon fangirl. She needs some Ganondorf stuff and a lot of Phantom Ganon materials, where I don't have all that many yet. I know that the new Reward Map battle has three of them, but I have yet to unlock this mission. Luckily the new Master Wind Waker Map seems to have a large portion of red and blue zones, where getting better materials from the new enemies could become easier.
On the Wii U she needs a lot of King Dodongo crystals and she's actually the third new character to do so, where she's the first new DLC character, where I couldn't afford all her badges right away. Luckily the Master Material Potion on the Wii U does a great job. I used it on the first Boss Challenge Battle with the ten King Dodongos and got nine gold materials out of it. They actually fixed the same potion with the current update for Legends, so it should work equally now, but it still costs way too much. 20 Silver Materials is nothing that I want to afford at this point. The Wii U version made much better use of the bronze materials, so you're not constantly stuck with 999 rubbish. And it seems like you can't get lots of silver materials from the "Divisive plan" battles anymore, which makes the whole situation on the 3DS even worse.
It's the similar with the Experience Potion. On the Wii U I used it together with Experience+ on the bottom left Master Quest square ("Rack up your K.O. count!" Lvl 12) and got Medli from Level 4 to to 37 in one go. Of course on the other hand there's still a long way to the 255 maximum with her... Which I probably won't do, because the real fun is on the 3DS with the new map and with less grinding. The Wii U version really lost all appeal to me at the moment and I probably will only use it to try out the new characters in full glory.