Excellent Post anothernewbie.
As a current Cathay DESO I can vouch for everything you've said.
With housing allowance paying off your mortgage (if you can afford the deposit), then CX is borderline worthwhile.
With no housing offered for Cadets, Cathay is simply not worth considering. I am serious when I say that you would be living below the poverty line.
The rumour of a future housing allowance for cadets is purely that.
Cathay has expanded the Cadet Scheme to save money. The whole point is that they don't want to pay you the same package that they would have to pay an experienced pilot.
Even if things are written in your contract, you still have to take CX to court to fight for it (eg Bypass Pay). There's no way Cathay will honour a rumour.
Happy Trails.
ULH