I think that's an excellent plan! I've always said that hour-building is the time to get a range of different experiences.....
In the US, I did my hour-building in Arizona, and can definitely recommend it as far as "local flora and fauna" is concerned, as well as recommending a very good school to rent from -
Chandler Air Service. Contrary to what biminiflyer says, no Visa is needed if you are just hour-building - the Visa is only a requirement if you are undergoing training. But you will need to get the ball rolling with regards to getting an FAA license - you'll need to pay the CAA a nominal amount for their efforts in confirming to the FAA that you do have a license. (The FAA don't make any charge for their efforts, though...)
No idea about Africa - I've heard some very good things, so long as you stay in the right parts of town, but no first-hand experience. But if you're planning on splitting the ATPLs, try to do the hour-building in between modules, immediately after the first set of exams.
Again, I'm going to disagree with biminiflyer on the last part of your hour-building - 5 hours is not enough. You won't need that much time to get back into the UK way of doing things, because as biminiflyer says, you've done your PPL over here. But you will need a little bit of time to get your general flying skills back up to the level where you are ready to start your CPL after a few months off. I think your plan is very sensible.
As for how to use your time, have a read of my CPL Diary (there's a link to it in the archive reference thread of this forum) to see what to expect for the CPL, then start brushing up on those things. Bear in mind, though, that the IMC requirements are much lower now than they were when I did my CPL, so concentrate on the VFR stuff.
Most importantly, though, have fun!
FFF
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