Our group came up with an interesting variant to make an already long melee even longer!.
The change is simple: we allow selling cards from a player's hand to other players. There are no rules regarding price - it is 100% negotiable between buyer and seller. We allow it only during during marshaling phase. Ability to sell cards is useful when you are trying to raise extra gold you need to buy something important and someone else just doesn't have any decent cards but has spare gold.