I actually prefer this type. As a woman, I like a nice weak man that I can save. I’d rather be the one wielding a sword and carrying him away on my white horse. Which is why I imagine this is just the authors preference. Kind of like most modern women wouldn’t like a story written like Cinderella or Snow White, with a man who falls in love with a woman for her face- and nothing else. But that was a true romance story a couple hundred years ago, and to some people it still is.
I don’t think it’s good for him to have no physical strengoth, but I’d like to point out why a holy sword/rapier wielding Eugene isn’t possible.
1. He is too frail in the sense that even running ends up taxing him. Even if he trained consistently, there is a limit to how much a person can improve in a year or two or so (the timeline for the main plot is about that much). He passes out from overextending himself at the drop of a hat. To go from that to a proper warrior is no easy feat. With the kind of warrior you desire for him to be, he would need atleast 5 to 6 years.
2. His use of holy power is mostly a magical burst. It’s not a consistent flow, but a nuclear detonation that also puts him out of commissions, sometimes for weeks or months. Once again this would require proper training to weird, but alexis asks him to not exert himself bc it always pushes him to be bedridden (any romantic partner would want the same). These long periods of being in a coma like state would impede and provide a setback to all physical and magical training.
There are definitely discrepancies between what you expect and what you get. Happens to me too, and often. Sometimes the premise of a story leads you to expect certain things, however the story itself doesn’t go in that direction. While it may be disappointing, Eugene’s actions make sense within the internal logic of the world. If you wish for the kind of story you described, there are many danmei which can fulfill your wish. The OP transmigrator in an mlm relationship what becomes an active fighting agent in his destiny is a particularly famous trope. I would suggest perusing novel updates.
on chapter 63 currently, but there are some issues i have with it that i feel like i have to address/or ask. like, eugene has brought up the topic his weak and frail body for some time now, but I'm currently seeing that he hadn’t made an effort to train at all? even he said so himself that it was an inconvenience, and that he had to train his body soon. i know that some people prefer the status quo (in Eugene's case, being weak and frail, because he has alexis to protect him) but with no effort, why even mention it at all from a writing perspective?
at the same time, i feel like there are too many instances of him being 'saved'. if the story was more focused on *his* character development, than alexis', no doubt we could’ve seen more potential with his holy power— like a holy swordsman. with that rapier, he could adapt a fast fighting technique, along with the fact that he has a light body too. he doesn’t need to be too strong, but he doesn't need to be constantly saved as well. it just makes the romance feel cheap.
not only that, it makes the plot unserious too. if eugene gets caught in a disaster, alexis would always be there to save him. and it's boring to be constantly showed that over and over again. if eugene is weak physically, but has a strong enough of a will to awaken holy power, show that he has a strong enough of a will to not get a fever/faint at every small thing. its tedious, and it's like his development stagnates.
tldr: good, satisfies my desire of reading/enjoying a fantasy reincarnation/transmigration with past memories bl, but eugene (yoojin) was terribly written, which makes the romance boring.