Hi Matt,
There are quite a few positions nowadays that are fully (civvy) Part 66 Licenced Engineers in the RAF. These are mainly on the larger stuff such as Voyager and the fleets at Waddington. The Atlas (A400M) will also be a Licenced Engineer fleet. You might notice that all these types are also civilian types.
However, even if you don't end up on a heavy fleet but on a Fast or just old fleet (or on the old fast fleet at Marham or the old slow fleet at Brize!) there are opportunities to study for whatever future career you want.
If you go to civvy Street for your career you will have a different experience but one that is likely to be just as enjoyable.
You have to decide two things:
1. Do I want to work on aeroplanes or helicopters?
2. Do I really want to join up?
Good Luck - whatever your decision
Rigga