The only time I've ever found any benefit in maintaining separate logbooks was when I was working for the MoD and doing a lot of military flying - they required a separate logbook. But even then all my military flying also went into my single personal logbook.
In my opinion your best bet is just have the whole lot in a single commercial logbook, AND have an electronic logbook. There are numerous commercial packages you can use, or write your own (I run mine in Excel). Or just run an electronic logbook - CAA are perfectly happy to be sent certified printouts for all and any purposes these days - they've not seen my handwritten logbook for my last 3 or 4 licence changes.
All flying experience is valid.