I agree with pretty much everything that
PAPI-74 says although I wouldn't agree that distance learning is a poor choice for your ATPL groundschool. I don't know anybody who has given up and gone full time - maybe some people just don't have the self discipline to work on their own? It is more difficult (especially if you're working full time) but it sounds like you're pretty focused so I can't imagine it would be a problem for you.
You can do large chunks of all this stuff in the US - don't bother doing your CPL in the UK it will take you a million years to get the right weather.
Definately agree that an FI rating is a good choice over a TR.....plenty of guys have paid for TRs and have no job as you need hours on type....just check current mins. for EZY, BA etc.... need hours on type.
Also, do you really need an IMC rating? The flying club will say yes as it gives you a basic intro to IF which will help you and save money in the IR. I'm not convinced about that - lots of practice with a good pc-based IF simulator will teach you what all the needles do and a few hours "under the hood" with an instructor should give you a good feel for it. Could save you a load of cash if you don't do it, although people will disagree with me.
Also, do you need a night qualification? Well, if you changed your mind and did an FAA PPL in the US you get night priviledges with it as you do some night instruction as part of the course. If you fly a few more hours while you're over there to make sure you comply with the night hours requirements prior to CPL issue (see LASORS for this - you need more x-country time, solo takes offs and landings etc.) then the CAA
might automatically credit you with a "night qualification" and even though you can't append this to an FAA PPL, you
might still be able to claim credit for the night hours required for CPL issue. CAVEAT - please check this first!!!!! I'm not 100% sure on it but it might be worth investigating.
You don't need a JAR PPL in order to commence a JAR CPL course either so I know it isn't in your plan but it might be something to think about.
Sorry to throw more alternatives into the ring but it could save you some cash and mean you get finished sooner!!