It doesn't really suit their usual network development strategy in the UK and would still be hugely limiting as to what route development opportunities could work from BHX.
I don't understand. At EDI all the MXP flights use frames based there, same for Venice and, in the summer, Basel. They could provide a range of city pairs using their continental bases, not just those already mentioned but also Geneva and Lisbon. If they avoid competing, at least for the moment, with Jet2 on the holiday business I think they could do well.
One factor not mentioned is that BRS is reaching its limit under existing permission, and looks unlikely to be allowed to expand soon. And on the Luton thread it is suggested that the airport may already be in breach of its existing limit.