This cannot be left alone. 100 minutes is too long to regen. You need to add a vitality boost to the guilds, at least. However you'll probably just give tiny boosts to top 5 instead (-2% for top 5 in next war! yay lets throw a few mountains to get that!). Or may let me craft potions instead of orb from all that awesome crafting material I never used because of its awesome awfulness.