You might find this post interesting/relevant: How much Japanese you need to understand different media formats (AKA data is fun) (I’d take it with a grain of salt)
As a general rule, I’ll almost always mark prose harder, unless it’s very difficult manga vs very easy (for me) prose, or some other specific factor. I’d say manga is often easier to read, and get the gyst, but sometimes harder to fully understand.
Factors I consider
- Number & complexity of vocab lookups (probably top factor)
- Archaic, fantasy, magic, other specialized vocab
- Unique vocab (plus domain specific, but also how varied is the “regular” vocab)
- Furigana vs not (tho sometimes furigana == harder grammar)
- Grammar complexity (manga grammar can be broken to the point of hard to understand)
- Difficult speech styles
- Is the speech very broken? dependent on implicit content? archaic or atypical patterns? dialects? etc
- Hard to tell who’s speaking?
- Hard to read out of box text
- Cultural knowledge required… manga I’ve read often has super specific references to pop culture (old and modern)
- Relative difficulty within genre (media type and content type)
- Is font hard to read
- Writing style (some LNs have unbearable internal monologue/narration, dense writing style, etc)
The reason I consider vocab highest is b/c it’s the most disruptive, and holding more than 1-2 words per sentence in your head, while trying to understand a sentence (esp the long ones) is very wearing. Work length is irrelevant - prose (besides short stories) is almost always longer than manga. (if it’s overly long b/c it really needed an editor, that’s a different story)
Examples:
Fate/kaleid liner プリズマ☆イリヤ 1 | L27 or ロード・エルメロイII世の事件簿 1 | L29 harder than ひげを剃る。そして女子高生を拾う。 | L26 (vocab and grammar(?))
- ひげひろ - can read/listen without stopping, with strong comprehension
- Prisma Ilya & El-Melloi - looking stuff up constantly, and still scratching my head
- lots of made up fantasy terms, odd kanji combinations, inside jokes, broken language, etc
- sometimes very abstract (esp El-Melloi)
Prisma Ilya/El-Melloi vs ソードアート・オンライン (series) | L33 - would give me pause, but SAO is harder
- SAO - can get through with decent comprehension (80-90%) but requires way more effort and vocab lookups than Prisma/El-Melloi
- Prisma/El-Melloi - I’ll probly have to check the translation a lot, but I’m holding way less in my head all at once
ボクガール 1 | L22 substantially easier than ひげひろ
暁のヨナ 1 | L27 similar to ひげひろ…
- Back in Oct 22 (when I first read AkaYona), Higehiro would have felt much harder. Now I’d find Higehiro more tiring, but AkaYona slightly more challenging (vocab, grammar, out-of-box text, figuring out who’s speaking, etc)
- AkaYona - tons of lookups (archaic language, fantasy stuff), extremely hard to read out-of-box text, speaker often has to be inferred, grammar can be tricky, speech varies between really broken and actual full sentences
- Higehiro - straightforward vocab and grammar, easier setting, fewer characters, etc
One thing that stands out to me is some of my evaluations are different now than when I was a beginner. Like if I tried Higehiro back when I first read AkaYona (2.25 years ago), it might have felt much harder. At this point, they’re similar difficulty (for different reasons)… which is not to say the either vantage point is more “objective” than the other.