Except when my proposal is demonstrably within the abilities of the admins (See Super Reflexes on Sentinels for evidence), and doesn't take anything away from anyone, since the new replacement power would be optional.
Whether it's technically possible is irrelevant, and no one said it was impossible. If you change one power solely to enable exploiting of set bonuses you're going against a cornerstone philosophy the game is built on. There is no reason Serum has to be replaced.
I think you need your reading comprehension upgraded. No replacement needed. Player can choose Serum still.
Either that or you don't actually understand the Cottage Rule.
You're not fooling anybody. The Cottage Rule isn't the cornerstone philosophy being violated by your suggestion, it's the balancing of sets around IOs that is. You just want a power that can accept pet IOs to use as a mule for the unique enhancements. Saying, "Oh, but Serum's still there for anyone who wants it, it's not being replaced," is a distinction without a difference; just being able to slot those IOs in some alternate power, even if it was as useless as Serum, makes it no choice at all which to pick.