They took away his CG because they wanted to differentiate him from Clark. Giving it back to him would likely defeat the purpose because then the only thing separating them really is DM's and NeoMaxes (and Ralf having a couple extra moves, which with his CG back, would contribute a lot less to his overall gameplay).
Instead, just make Ralf better, make his pokes do more damage. If the devs want him to be played a lot like 98 Ralf which seems to be the case, they need to make his pokes a lot more meaningful in the long run akin to how 98 was played.