I find the difficulty in Touhou labyrinth to be just plain better. Is better harder? is it easier? It's complicated...
As Trance already stated, immunize (and fortify IIRC...Immunice moreso though, both..lol) makes the game go from zomg I'm being 1-shot by this boss' weakest attacks! to Zomg I can kill the boss before needing to heal a single time because I'm taking so little damage! Even excluding those two moves, each class generally has some skills that are just so much more superior than their alternatives. So basically both EO 1 and 2 are massively harder than Touhou Labyrinth until you reach that threshold of "getting the good skills" for each of your character (generally you just need 1 for 2+ of your characters in your party before the difficulty goes from omgwtfhard to normal, and shortly after that it's a total snorefest).
EO2 doesn't suffer from "power skills" nearly as much as EO1, but it's definately the same situation, extremely difficult at the start, moderate afterwards, then pretty quickly it becomes really damn easy.
EO also has post-game content that is scaled for the level caps pretty much, but I can't really comment much on that. Seems that after I beat the game, I dip my feet into the post game content and it still remains too easy IMO. The super mega final bosses are notoriously hard, but from w hat I hear it's not real difficulty so much as you MUST follow this EXACT strategy to win, which really doesn't sound like much fun to me.
They are definately worth trying though, I think they are pretty fun until you get near the level caps to be honest.