OzzyOzBorn
There is obviously this rumour about Ryanair and Easyjet being offered exclusive use of T1/T3, however true it may be, but I just don't see that MAG see the existing T1 building as forming part of the future solution. The next priorities for the TP were going to be the refurb of the existing T2, and the completion of Pier 2. The reality is that there's no money at the moment, but if any does become available, I'd think they'll get far more bang for their buck by advancing the plans that are already in place. My understanding was that the scale of what was proposed for the T2 refurb was fairly substantial - I'd expect to see that scaled back, but some sort of viable solution to have the constituent parts of T2 operate as a single facility to be achieved. T2 (or certainly the new build section) is pretty well set up for bussing passengers now, and as businessair75 mentioned above, it seems that the plan was for EZY (along with the other remaining T1 tenants) to move over to T2 in the next 18 months or so anyway. Probably a (the?) big sticking point of this is that the T2 refurb would've been based on an expansion of retail in that area, which I'd think would be difficult to achieve without the substantial works that were proposed, and thus they'd be losing out on retail revenue by closing T1.
I do see the merit in what you're suggesting but I think that if T1 does survive for the time being then it's very likely to be, more or less, in its existing format, as opposed to with any substantial changes.