The main "solid feature" of (a popular GBA ROM hack often associated with the Pokemon FireRed base) is its comprehensive roster and revamped mechanics that make it feel like a modern Digimon RPG rather than just a "skin." Key features that make this version better include:

The early 2000s was a great time for fans of digital monsters, with both Pokémon and Digimon vying for the attention of gamers around the world. While Pokémon was (and still is) a household name, Digimon had its own loyal following, and one game that still holds up today is Digimon Reload for the Game Boy Advance (GBA). Released in 2004, Digimon Reload offered a unique experience that set it apart from other monster-collecting games of its time, including its own series' more popular titles.

If you're stuck, let me know which you're most excited to use! Digimon Reload (Hackrom GBA) - Facebook