Assuming you want to break packs...
1. Visibility: if you can see someone of anyone close to your standard, and they are navigating you can catch them. As a planner you have to break line-of sight - then its surprising how much the hesitation this causes can break the link.
2. Butterflies: fine for splitting pairs of runners from an interval start, but pointless to break groups of 20 into two groups of 10, especially since the upcoming butterfly is marked on the map (Hagaby-type gaffling, or allowing everyone to miss out a control, works much better).
3. Route Choice: doesn't help early on as the safest route is always "the way everyone else is going". I was surprised we didn't get more route choice though - there's scope for over-or-round or a massive NE-SW leg crossing the whole area.
4. Long legs: could have helped, allowing the leaders to switch off and run might have been
enough to let them get clear. Also, you need to offer the possibility of gaining over a minute (i.e. well out of line-of-sight) to tempt people into taking a different route.
On the other hand, maybe you don't want to break packs. I found it an enjoyable competition to take part in: somewhere midway between trail racing and orienteering. It tested different things from regular orienteering, which benefited some people more than others. If we don't embrace this type of competition, BOF could well find another competitor for our attention, alongside adventure racing, MTBO and mountain marathons.
Now, if only I could sprint and remember to visit all the controls...

Graeme
PS I thought the planning on Saturday was excellent -the area offered lots of scope to make the race a lottery by hiding flags, or tedious with all-legs the same length: they did well to avoid that.