Are there any guidelines for setting the hose length for a front brake? On the rear I've enough spare hose to allow the bars to completely spin without ripping out the hose, but the front brake doesn't have that problem.
Obviously a large loop of hose waiting to be snared on something isn't a great idea so I've cut it fairly short whilst still allowing a natural curve of hose from the lever (so no forced kinks).
You can normally spin the bars one way and catch the front. My advice is long enough that it sits naturally with your other hoses, ie doesnt diev straight from bar to fork, but isnt so floppy it wants to droop away from the main cable group.
The other thing to consider is whether or not you might want to use a barbag of some sort. You'll often want longer cables.