If you want to fly more than you want to join a specific service, then I would suggest being open to the potential of flying in any of the services. I only say this because whilst all services have similar requirements in terms of leadership and personal qualities, they did at least weigh their aptitude tests differently.
For example, when I was going through the application process, oh God was it that long ago?, the RAF required you to get a score of something like 110+ to pass for pilot, whereas the AAC only needed 90+. So, all things like medical, leadership and personal qualities and slots available being equal, if it's just about getting up in the air, you might want to consider all options. Just be prepared to answer the inevitable question of "so you've tried for X 3 times and failed and now you've come to us???"