I don't think he needs CT levels of damage back, but I'll be damned if he shouldn't be doing the some of most combo damage, being y'know, a damn grappler and all. Not being outdamaged by a good portion of the cast, espicially with dumb shit like Bang's 5A in nearly equal damage to a full Tager magnetism combo and Litchi's 4K off of anything into silly corner oki or Ragna;s 4K BE loop combos. That's should be his tradeoff for such crappy mobility.
Like say, slap on an extra .5 to 1K on his magnetism combos via proation changes, and reduce some of the damage from the others, and it's fine IMO.