You should be hitting Level 100 by the time you get to the Elite Four.

Every trainer in the game has been edited, and the level curve expects use of the Experience Share, which means that you level up very quickly. The premier feature of Rutile Ruby and Star Sapphire is the ground-up redesign of Pokémon Trainers in the world to increase the game’s challenge.

Their main purpose is to provide a more challenging game experience while not artificially limiting the player. Pokémon Rutile Ruby and Star Sapphire are ROM hacks of Pokémon Omega Ruby and Alpha Sapphire.