If you're that keen on a specific hour building program, then I'd say you should be looking at one of the sausage-factory ATPL producers, who have set courses and syllabi for the 100 or so hours between PPL and CPL.
If it's an 'expedition', I don't think you'd see much difference between doing it as a 'joy of it' PPL, or an 'hour builder'. You'd want to mix in a range of different aiport types, from grass strips to international controlled airports, for the practice. Pay particular attention to your stopwatch/compass nav, and keeping course to within a couple of degrees and altitude to 50 or so feet as these are much more strictly tested on the CPL than the PPL. Don't allow yourself to fall into the GPS 'trap' - I find that when I have it, I have to be much more disciplined to try and keep my traditional nav skills up to scratch. Always have one as a backup though, but be strict with yourself.
In addition to your trip, keep some hours in hand for practicing PFLs, stalls, circuits etc to a high standard. Maybe make your legs on your trip in one direction very short, to maximise the practise in airfield procedures, and practise some long cross country nav on the return journey, or vice versa.
Whatever you end up doing for these hours, just make sure you never give yourself a break - debreif yourself after each flight and make a note of every mistake, so you can avoid it next time.
Most of all, have fun!