D-C: JF made a good point or two, as always.
As regards the administrative requirements, breadth of experience is useful but I think you'll find that you will need to have completed at least one operational tour and be assessed as Above Average in flying abilities to be eligible to apply for an ETPS course.
Your Aero Eng degree will be useful...mainly for the Groundschool phase.
For the moment work hard at your flying, be self-critical BUT enjoy it too. Single-mindedness and dedication may help you achieve your goal.
So finally, whilst echoing JF's thoughts on vocation, it's true that ETPS and the years that follow must be the best posting you're ever likely to get in your RAF career.
Good luck.