I don't think Madrid or Manchester would be helpful. The first would be jumping on a new route by a new carrier. The second would undermine EI Regional; we only need to look at Shannon to see how that can go.
I'd happily take any of the others though.
Would Ryanair be interested in Lisbon? Route supports will be available again quite soon. Couldn't see it as a Winter route though. Nice is another summer route that might suite them.
There could be potential for Milan to go year-round if they could target some skiing traffic.