Hi, even more late to the party. As I said on the Sunken Spire page, I played this afterwards.
Gameplay...
...was overall pretty fun, and I liked the focus on singular encounters, but like Sunken Spire it was really easy and unbalanced, even on hard mode. Evvy and Alan were particularly gamebreaking. Evvy was immensely useful because indirect healing and damage seem like the most effective strategies; there's nothing enemies can really do to counter them, and they continue working even if everyone's incapacitated. (Elias is also useful because of this.) If you set up enough thorns, all you have to do is wait and the enemy will die eventually. Meanwhile Alan is practically invincible if he guards every turn, and at level 2 he can keep attacking even if he does that. Then at level 3 he gets amazing offense too! I honestly don't see how the hard mode final boss is possible without him.
Everyone else was pretty meh. I was sentimental towards Tira Misu since she was the first party member I got, but her need to replenish her stocks slows her down too much and she's way too fragile to make up for it. Ruby just doesn't seem very useful in general because she burns out too quickly and recharges too slowly, which runs counter to a system that incentivizes building up EX before unleashing strong attacks. Argos is in the wrong game. I never even used the royals, though Albert might be a possible substitute for Alan if you need defense I guess? Victoria just seems like a poor man's Elias, though, since her indirect damage can't accumulate. Garron is the only other one who's really decent and I used him a few times (that stun attack is particularly good), but with only three party slots he just can't compete with Evvy, Elias, and Alan.
The EX system was...hm. I presume you did it to discourage turtling and accelerate the pace of combat, which I'm generally in favor of, but I worry you might have overdone it. It kind of turns battles into a binary thing; everyone grows in power so quickly that either the fight is over almost as soon as it begins, or you're screwed because the enemies will oneshot you before you can strike back by virtue of their having more health. And there's no way to manage it outside of Carmen and Garron, and Carmen's skill never seemed to work for me. I think this would have worked better if you didn't have healing and gave the heroes comparable hit points to the monsters, or if the values didn't climb quite so fast. Or if you weren't constrained by the godawful default battle system and players could actually react to attacks properly instead of choosing someone to heal at random and praying they picked right grharaghgh why did Enterbrain ever think that was a good idea.
The zombie dragon was clever, though. I love it when RPGs do stuff that lets you use the full party like that. Even still, I beat him on hard mode before he was even halfway through my reserves.
Storywise:
Kiiiinda uncomfortable that you used the bog-standard "ice queen who thinks she's independent but finds ~true love~ after all" cliche. But, despite the trope's inherent issues, I think you handled it well: The focus is solidly on it being her choice, you have a man in the same situation, and it only happens if the player actually works towards a believable relationship rather than housewifery being her destiny. Plus her career still takes precedence over her relationship, making Gideon more of a "bonus prize", which is good because that's usually how the gender-flipped version works. But...it's still pretty awkward to have the whole story be about people trying to force her into marriage, her expressing disgust at the idea, and then realizing that's what she wants anyway. I get that people like true love stories and all, but as an aromantic person it's just unrelatable and cliche to me, no matter how technically well-written.
Elsa's character was also a lot more shallow than she was in Sunken Spire, even if that does make sense. In SS I felt she had more nuance to her; she was still the boisterous tough guy with a soft side, but I thought she was more confident and comfortable with herself -- just more mature in general, and having her soft side be motherly rather than romantic was a sensible outgrowth of that that's a bit different that what we normally see in the archetype. Here, her snarky side is just so incredibly over-the-top that she sounds like a child trying to compensate for her insecurities, which makes the contrast with her blushing girlfriend side even starker and weirder, like it's a completely different side of her rather than a logical facet of her personality. Well...the date scenes were actually pretty good, but the resolution where they're both blushing daintily and stumbling over their words was a bit much. It's possible that was the point, and taken together with SS it does make sense as a character progression, but I still felt she was weaker here.
Also, bratty princess + wise prince is similarly awkward, but I suppose it is counterbalanced by idiot king/competent queen. Still, might have worked better if Elias was a woman, to avoid the "willful emotional girl has to be kept in line by a man" implication, even if it was slight. (I did love the contrast in their equipment descriptions, though.)
But overall, pretty good. I liked the shadow siblings, they were cute. Fighting them all at once for the penultimate boss was cool, and one of the few difficult fights in the game (even though Moumi doesn't work very well in a group).
I noticed quite a few typos, though, as well as a few lines that went over the message box length. The game could have benefited from more proofreading, but given that it was a quick contest entry I can understand some sloppiness. The most awkward was probably "A potato dies horrible" in the result message for the peel skill.
Edit: Hid things behind spoiler boxes to mitigate the walls of text.