I feel like you're at the very least misinterpreting what happened in the Lotus Eaters scene between Reimu and Yuugi.
First off, I don't think of Reimu as the type to just get into fights for the hell of it, she's the kind of person that only fights when she feels an incident is going on. Miyoi? Definitely not the type of character to get in a fight for the hell of it and doesn't want Yuugi and Reimu to fight.
Yuugi? The complete opposite, she might be the most gung-ho for a fight character of the entire cast, and she creates a scenario where she can 1. Look like an obstacle that is necessary to overcome to Reimu solving an incident, 2. tries to create a sense genuine danger, and 3. does her level best to pick a fight to the point that she gets annoyed when Miyoi ruins her plan by revealing herself to be OK and not in any danger.
Like, be disappointed at the fight itself not happening, but you fundamentally misunderstood the scene, or at the very least Miyoi's character, if you thought it was a contrived reason to not have a fight. And I think that's what happened considering Suika's not merely not involved in making sure no fight takes place, she's not even in the scene or in the Underground at the time of the scene.
I was misremembering that arc because I read it 4 months ago. That's why I misremembered some details like Suika being there when she wasn't and other stuff. I just re-read that arc to refresh my mind and I must say that I forgot several details and I was speaking out of my arse.
That being said, I dislike that chapter. It had the tensions that would have normally led to a fight but Miyoi appeared and talked things out. What a bummer. I would have preferred if they fought.
That and things like that happening are not unusual in the series. When there is enough tension for a fight to break out, a character conveniently comes out of nowhere and talks things through. And the few times a fight occurs, it ends quickly and the fight is boring. That Reimu and Yuugi situation was just the first "Event that would have been a fight but didn't turn into a fight because the plot demands it to" was just the first example that came to my mind. It was one of the moments that made me throw my phone (Against the bed because these things ain't cheap) out of disappointment. I'm a fictional fight-oholic after all.
I think it's fine that the mangas don't do fights very often. We have over 20 games dedicated to these girls beating the hell out of each other, the manga are likely intended to NOT be about fighting as a way of distinguishing them from the games.
The difference between the mangas and the games is that I believe manga is a better method of showing how the characters would canonically brawl. I don't know exactly how to put it in words but you can't compare a manga fight against a video game boss fight. Those things are completely different and feel different. Do you get what I mean or did I express myself in a confusing way?
what’s your favorite touhou manga?
Well,
Lotus Eater is mediocre, I don't like the genre a lot but it's not bad per see.
Wild and Hornet Hermit is mediocre too, though I'd say I like that one more than LE.
Cheating Detective Satori is a disappointment and has a lot of wasted potential. Why the hell is Satori, the girl named after the manga, barely a character in the manga? Her personality is boring and she doesn't do a lot. She should do more, talk more, be interesting, but no. That and I can't forgive ZUN for that short-ass Mokou v Mizuchi fight. Mokou did her strongest direct feat and after that, she started jobbing to Mizuchi and got instantly possessed. Unforgivable! CDS is the only manga that I think it's bad out of all the ones I'm reading.
Silent Sinner in Blue might be the one I like the most. I am a sucker for cool demonstrations of a character's strength, abilities, and speed and that manga has those. I jumped out of my chair once I saw the best girl, Yorihime counteract lightspeed attacks. The fights in that manga as a whole had me pogging. It's one of the few Touhou manga that made me feel something that isn't indifference or hate so I liked it a lot.