> on the other hand, i've also come across webpages which say don't mess
> around! keep the defaults as they are unless you are absolutely sure
> that changing it suits your purpose and know why.
I would do it exactly that way. XFS works reasonably well for all
ordinary things with the defaults (under the assumption that you are
using a reasonably up-to-date version of xfsprogs i.e. mkfs.xfs) and you
shouldn't fiddle with them unless you have very good reasons doing so.
Considering your current load on the server it shouldn't matter at all
and staying with the defaults is also a good way to ensure people will
be able to reproduce problems and help you in case you run into problems.
Just my 2cents