Makai is harder by far.
Ok, Jigoku has Kikuri whose first phase is possibly the hardest attack in the game, but all other Jigoku bosses are easier than the respective Makai bosses. Also, Stage 19. Just... Stage 19.
Canon? Well, I'd say Makai.
Why?
Because the Jigoku ending whatisthisidonteven?!
You might have a point in that the non-boss stages of Jigoku are harder than the Makai ones in general, especially on lunatic, but what matters the most in the end is the final stages. And there, well...
-Sariel is (usually) much harder than Konngara
-You effortlessy get max lives in Jigoku stage 19
Also, Jigoku is obviously the canon route because Reimu had met Mima before HRtP.Hmm, you have a point there, but... the ending... what is happening there? And no, not knowing japanese is no excuse, the little text that's there can't possibly explain what's going on.
I like to think there's a way for both to happen at the same time though.Totally agreed.