Speaking of Simon's Quest, I have a really great homebrew modification for that game on EMU. It's still the same game, but it offers a number of improvements that make the game playable for English speaking audiences.
It had a save system and not a passcode system. On EMU, save states make this largely unimportant but there are some that have put the ROM on a cart to provide a more authentic experience.
Near perfect English translation so that the dialogue makes sense and is actually useful.
An in game map of the world that can be accessed at will with the Select button. And surprisingly enough, it's a very well drawn map.
An opening 'film reel' sequence that explains what happened in the first game and contextualizes the story behind the second game.
The ability to switch between weapons and whip types. In the original build, you were stuck with whatever whip you bought last, which could be frustrating and needlessly grindy. This way, you can just change the equipped weapon for maximum efficiency.
My file shows it as 'Castlevania II-Retranslated with Enhancements' If you haven't tried it yet, I'd recommend you give it a spin. It's an interesting version and who knows how things might have gone had the NES release not been so clumsy.
I don't feel this made the game 'easy' so much as it made it 'playable' and a satisfying Castlevania experience. While it is a non linear game and there are RPG elements in it, Castlevania III didn't try to carry that formula forward (which I think was the right move at that time). Instead, it returned to the more traditional platforming of the first game with some alternate path choices as well as your option of which companion to bring with you on your journey. Or, alternately, you could just go it alone the whole way. The game has four different endings depending on which companion you beat the game with (or none at all) too.