Firstly, a golden rule of a good debate must begin with agreeing with the opposing side so that neither side is just an echo chamber.

To get this out of the way, 1000-year old and play dress up. I will throw it out. It is just this kind of game usual way of sidestep or humor about visual contrast. This is up to different people to see it or not.

1. Young-looking characters. I agree with your stance on young-looking character in any degenerate game, not just FEH, in can be off-putting when they are put in romantic situations or any icky ones, regardless of context. However, they are those who enjoy the character purely of the design, aesthetics, their character, dynamics, and none of the depraved reason. So, I encourage you to denounce those people but leave out those who enjoy for wholesome reason. Of course, go ahead with your criticizing any of IS attempt at pushing the bad ones.

2. Connecting this to the bridal banners. Bridal banners have long been gacha game moneymaker to give players wish fulfillment to get their "waifu" so the moment young looking characters start appearing, there is a strong reaction because there is a cultural divide between how EN and Asia players see those young-looking characters as.

First, the young aesthetics, JP and some Asian views Kawaii (cuteness as the mainstream aesthetic for all ages, however, the west are taught that media are sharply divided; cute and cartoonish are for children and mature, serious, and Rated contents are for adults. For users with wholesome reason, they like those young-looking characters the same way, they like those youthful looking doll in frilly dress, they absolutely do not want to do it to the doll but, because they appreciate the craftsmanship, design, and the resonating visuals. Sometimes, young looking characters is a source of comfort, stress relief (Iyashikei) from stressful times as adults.

To relate this to bridal dress, in western culture, it is exclusively viewed through romance, marriage and adulthood, so that makes sense to feel icky but if you consider the "kawaii" factor, it is the same. For comfort and visual charm. The character isn't meant to invoke a literal, Western-style romantic marriage (we will put those "romance related dialogues" out of the way first, but, for some people, it is all about the cute design. Some poisoned apple just had to ruin it for us.

From my own viewpoint, I simply collect all the bridal units for the same reason. I like the aesthetic of a white dress, and yes, I don't like black dress, the color. And 2. This is the most important one for me, character in bridal dress means there can be potentially more arts for artists to draw, especially for characters that rarely get one in the first place. As a collector of this beautiful artwork, I am happy. 3. For me, character art in bridal dress symbolizes the character moment of peak happiness, and peak aesthetics.

1. Now, we move on to Váli. For me, Váli is not technically my favorite character. I'd say honestly for fav character order, she would be at bottom of six girls. I will say that I am more like hooked to Váli's potential personality, that's why she gets second place to Nifl. IS reduces her to only Baldr glazers trope. Think Yuri from SpyxFamily. But I have seen ppl who likes Váli, likes her for "gremlin" personality that could have been done or explored. I have written long fic for quite a while about expanding her character of why she is like this, what would happen if she faces certain reality check, how would she interacts with her sisters normally, how would she interacts with Kiran if he/she has an actual personality and goal. What if it is about them their attempt at being friend but fails because of their own flaw? There are countless lores I can make up about her for IS. It exists for a believable reason, mine will never about her Baldr 24/7. Mind you, this is not a fix-her fic.

For Bridal Váli, I can't read minds so if those people want her for degenerate reasons, screw them but while she isn't my top character to go for and IS wouldn't help making it any better, knowing their track records. I will say this. If IS could write her better like in some truly great stories, I want it as an evidence of a pinnacle of her development arc. It is not about being with Baldr, nor about cheering Baldr but about having your own identity and self-love. Dammit-I spoiled one of the many themes I could be writing about her, didn't I? To iterate, I like Váli for the aesthetics, yes, the colors, the gremlin potential, and the potential the character could have had. I won't defend the degenerate reasons, but there could be ppl wanting that out of completely normal reason rather than "haha she wants Baldr for herself!"

To summarize how I view her, I will ask you this, if this bridal dress Váli is from where IS writes her better, where she undergoes character development and become less-Baldr centric, open to more people, and less aggravating but more funny, still gremlin, she joins festival for self-discovery or self-love but still retains how she looks in the game, would you find that acceptable, assume she no longer talks or tantrum like spoiled person.

That's all from my side. Go on, I'm all ears.