Mana regen scaling for support items?

I got this idea while thinking about how certain champion abuse items such as and . Saw a few gameplays already were 3 champion on one team built redemption or solari. These are items that should be built by supports only imo. So what could be changed about these items? There are scalings for almost everything in the game. Certain champion scale with ap, ad, mana, armor, magic resist etc. But there is nothing really that scales with mana regen. What if items such as redemption and solari were nerfed in base heal/shielding but get a mana regen scaling. Most supports build items with mana regen anyways etc. They would synergize pretty well with it. It's just a thought What do you think about it? Could it be abused too? Would there be a heavy downside to the changes?