You don't need to do any hours to keep your licence current here, just a flight review every two years to exercise the privileges and I am presuming that hours you do here would count towards a Certificate of Experience there (if there is still such a thing?)
My advice would be to build up to say a total of 175 hours here, get as much command time as you can, then decide if you want to stay here or fly in the UK. You should be able to do a modular course over there if you decide to go back. It's been a while since I was instructing there so things may be different now
You don't need to do a "CPL course" here, just have the required hours and then whatever training is required to ensure you have the competencies required for the CPL test. Competencies that aren't any different to PPL but just with tighter tolerances.
If you want to do bush flying there is always work in aerial survey. As they have just announced that the govt is planning to map the entire country I'd say that could be a big growth area in aviation and a lot of people who do airline style integrated courses wouldn't really be suited for that kind of work. PM me if you want more info.