A330 based at LHR; tell us more, Silver Tongued Cavalier!!!
Frankly, I would not be surprised to see EI out of oneworld, although I do see a benefit in continuing its relationship with AA to the US and also of developing a relationship with CX in Asia. I've always felt HKG would be by far the best hub in Asia for EI, but they'd really need to get moving on that, before EK finally gets its act together and starts serving DUB.
As for feeding BA at LHR, I agree totally. There have been rumours that the A321s are on their way out and if this is the case, notwithstanding the larger capacity of the newer (vs. the older 320s), EI will probably want to focus on point to point for flights to LHR and develop its own long haul links. I can't imagine that the yield from pax on long haul connecting pax would be worth much to them.