Given development of late, I am pretty sure the answer is 'metadata as much as possible'. Anybody who tried a messed of Windows registry also knows who centralized things can suck at times :-p.
Thas single argument sold me right away! It's also rather "oldskool" to try and preserve the little diskspace that centralisation saves, given that disk space is rather cheap these days. And as you said, local is portable.
Andreas