We've already been through that it shouldn't.
And no. Infinite mass-CC is better than a slow-ass redundant (since the Retrovirus deaths and opponent creature deaths will be more than enough already) combo 95% of the time. I still stand by infinite Retrovirus generation being too strong, btw. Since Plague is already only used in stall decks, this upped card would basically replace both Retrovirus and Improved Plague.