Hello and welcome to Feedback Quest 9! My name is Hythrain, and I'm one of the hosts for this lovely event! I'm also one of the streamers, so both the game and this feedback are being done live! If you want to see the see the VOD, let me know and I'll link you to it when it's uploaded to YouTube!
This is probably one of the most unique tower defense games I've seen, employing actual characters instead of actual towers and adding in RPG elements. It was a lot of fun to try out! I was also really impressed with some parts of foresight I saw, specifically how you thought about menu switching between the shop and the character screen while on the map (I found I could hit the two buttons on the bottom back and forth and it never broke anything).
Since this is also part visual novel, I did keep a mental note while playing to try and catch things that I normally do with other visual novels. There was one line where I thought it could use a rewrite (the line in the opening about an elven man, which I felt should remove the second use of the word "cave" to make it not feel as repetitive), and there was one general thing I wish the story had done: I wish character names weren't given to the player automatically until the name was said out loud. That way, players have to be introduced to characters. What could help facilitate this is a tweak to the beginning where it's the guildmaster's first day and they're first introduced to Yuki, then to Ragnar and Luna as needed. Once a character's name is said, whether from someone properly introducing themselves (as Aelwyn does later on) or from their name coming up in the conversation (much like how Yuki invokes Luna's name very early on, which could then act as the "introduction"), then it can be shown in narration dialogue. That way, names aren't revealed by narration before the player knows them.
In terms of the gameplay, one thing I found rather frustrating was how the only character I was ever able to start with was Yuki. While this makes sense and is fine in the first few levels, you eventually get to a point where, unless you specifically are giving all of the gear and talent points you get specifically to Yuki, she starts getting her ass kicked before you can really build your group up. In some fights, you really need two or even three characters to prevent someone from dying from the first enemies. I think the best way to resolve this would be to either given the player higher starting deployment points or to reduce the amount of deployment points needed for each character before you begin the level. It could even be done where specific fights encourage deploying specific characters first. As an example, the first fight with Valessia could be set up where she and Aelwyn take less points than other characters, making it a smart move to start with them. The logic behind it could be that because you're in the heart of elven territory, they know the land better and can thus be deployed faster.
I also found that the rate of gold feels really slow. I don't know if you plan to add more equipment down the road or if what the shop has will be everything it ever has, but it was taking 3-4 fights for me to buy anything. While I know I can get money from losses, I'd much rather just have it I get more money from winning and to have a better pace of gear. A higher money rate could also allow you to weaken starting items and to add more powerful stuff later in the game, fitting better with the RPG elements.
Lastly, I feel the design for the talent trees is a little awkward. They're based on weapons, but there's no visual consistency on where you start. You just have to find the one small icon that's glowing. While doing the weapon thing is a cool visual concept, I think it should be designed in such a way to remain visually consistent. For example, where the early talents start on the left or bottom and work their way right or up regardless of the weapon. That way, the player doesn't need to fumble around to figure out where the starting talent is for each character.
That's all I have! I hope to see more of this!