Pauljp has one of his nice videos on that: https://www.youtube.com/watch?v=kPmDkg6rc6w
I don't have a fuse block on my XCT (although I do use Powerlet's Termin-8, in order not to glom up battery bolts), but I did do that on some prior bikes. My general advice is to put it where most of the action is, in order to minimize the wires runs from it.
For instance, if you add extra lights on the forks and a horn in the fairing, it seems to make sense to put the block in the fairing, too.
Similarly, if you're adding a lot of action to the back or middle of a bike -- license-frame lights, flashing brake lights, maybe some LED strips -- then you might want to find space under a side cover or under the seat (which is not so well suited for our Vics, but works for a lot of other bikes).
For every wire that crosses the neck of the bike, you have to make sure there's adequate slack and that it doesn't get pinched in lock-to-lock handlebar turns.
I wouldn't base a decision on how easy it is to replace a fuse, because if you do your wiring right replacing a fuse should be a rare or non-existent event.