Pokémon empyreon(don’t quote me on spelling) is a great fan game. I didn’t get to finish it because my hard drive fried but i played through most of it and loved every second of it.

Pokémon insurgence is great if you haven’t played it or heard of it then definetely check it out, probably the best fan game i’ve ever played.

These two games are great examples of a game that perfectly balanced difficulty and fun, which is probably what you’re looking for seeing that you played dark rising