I'm running it differently from the GW4. Firstly if someone states they are challenging, follow the rules, but we meet and it's more pairing off, in those circumstances the players can choose each others.
Lastly, because I like it and the players seem to like the idea I've added they can up the stakes, which is where someone is challenged ups the stakes and counter challenges for one of the opponents territory, meaning there can be bigger swings. Effectively making territories like poker chips, so multi games can work too as it's a pot (though I'd assign which territory everyone is player for in those big games).
