Hi Thomas,
For what it is worth, I know of several military crewmen and engineers who have gone through military pilot training and have made very good pilots.
Obviously, your case is a little different as you are having to find ways to fund yourself through training. You previous expereince may or may not be recognised by any future employer, but I feel that you will have a distinct advantage as your previous enigineering and crew member experience will make
you more aware as to what the rest of the crew are experiencing and therefore a better pilot.
Best of luck. Don't give up on your dream - despite working in (and sometimes below) the cabin, when I am flying it is still the best job in the world.