For romance, check the dialogue rhythm
Romance manga often depends on conversation rhythm more than the setting alone.
In the preview, look at distance between the main characters, line density, and the first chapter hook. A soft tone, slow build, or fast banter will lead to different choices.
Separate slice of life and fantasy by reading context
Slice of life manga tends to work well in shorter reading sessions. Fantasy and isekai stories often reward longer reading time and setting details.
If you want a quick commute read, start with slice of life. If you want a weekend session, fantasy or adventure may fit better.
For suspense, check volume count first
Suspense and mystery manga can be hard to pause, so volume count and completion status matter early.
Decide whether you want to follow an ongoing series or read to the end, then check official store pages for volume count, latest volume, and preview pages.