Your plan certainly sounds sensible to me. However, as someone who's nearly half way through the distance learning course at Bristol, I'd suggest you do the ATPL exams full-time. I'm unable to do this, because I have to work full time in order to pay the bills - but distance learning really is hard work, and if you can afford the time and the money I'd definitely go for full-time studying.
Having said that, if you do decide to go for distance learning, Bristol is an excellent choice, IMHO. But you'll need to get the PPL sorted out before you start worrying about that too much.
Good luck!
FFF
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