I very much doubt that DESO and DEFO will ever come back if the AE and TT guys don't have too much trouble upgrading to FO.
You can write what you like but last time I looked half the world's economies are in the toilet and thousands of people (not just with 250 hours but hundreds of people with significant jet time) are out of work. In most of western Europe this trend is set to continue for the next few years at least.
By taking the package people are pulling down pilot T & C's I hear you say. No because a lot of airlines are already doing that very effectively. The Cathay deal is nowhere near the worst deal out there. Ryanair who ask you to pay 30k Euro for a type rating then make you a contractor who may pay you as little as 1500 Euro a month comes to mind. American regional's where the starting pay for an FO can be as little as 16k USD a year also comes up.
B scale is never coming back neither is the large housing allowance. Just let it go.