I’ve had some hard battles and had most of my team wiped out due to tired Pokémon or just plain awful team spread. Overall, it hasn’t been challenging, but neither was Blue (unless you picked Charmander to start). This is much more fun, has a better inventory and Pokémon management system and I’m finding it an excellent refresher course in why this series is so god damn great.
TL;DR — I enjoy collecting the Pokémon and the story is glorious fun but kind of plays second fiddle to the Pokédex. Gotta catch ‘em all!
Edit: also, where the hell do you find Eevee in the Pikachu edition?