I think it's an historical fact that flight instructors have never been in demand anywhere except in such small blips that only those on the ground ever get to hear of it.
I think it's also true to say that flying pay for any pilot outside of major carriers is pretty dismal and that the remuneration for flying instructors is the worst of the lot. You generally only get paid for the hours you fly and each session of flight requires a pre flight brief and a de-brief. That's professionally speaking, you understand. Can you live solo on a full time flight instructor pay? Generally speaking, yes, but you've got to get that job in the first place.
Then there's the problem of work permits and visas which, generally speaking, for Australia at least, can be tricky to obtain.
All might not be crash and burn though because it seems to me that there is often an international requirement for ATCOs with good add on qualifications. You know the ones, area, approach, aerodrome and so on.
In England you can instruct on a PPL and that's an easier route than the Com licence required in South Africa and, I think, in Australia. Perhaps a round about route might be in interesting subject for research?
The best of luck to you though. The route you outlined takes true grit and perhaps two years at least. You've got the bucks and the determination and the stability of marriage (I hope). You'd stand out in the crowd at an interview as a dedicated self improver and that counts for a lot when the jobs get doled out.