Coincidentally with my Troop management tip, post-1.0.7 I’ve leveled every kingdom to 2.
Say you have 19 kingdoms, one of which is above level 1, and you’re aiming to get that one to 10 first. It only costs 9,000 gold to level 18 kingdoms to level 2 which doubles your tribute income. That’s not much of a dent in the 122,500 gold you need to get to level 10.
Of course, the more often you get the hourly tribute check, the more sense this makes.
I wonder where the break-even point is. 18,000 to get all kingdoms to level 3 doesn’t sound that expensive considering how many tributes you’ll collect on the way toward leveling several kingdoms to 10.
If all you care about from tributes is gold, then just apply the above thinking to the good gold-producers:
Kingdom Name Gem Mastery Stat Bonus at L10 Tribute Rewards
Gold Glory Souls
Khaziel Brown Life 250 0 0
Broken Spire Brown Life 200 0 4
Stormheim Blue Life 200 2 0
Adana Yellow Armor 175 2 2
Maugrim Woods Green Life 150 2 4
Zaejin Green Life 150 3 2
Sword's Edge Blue Armor 125 5 0
Mist of Scales Red Life 125 0 10
Pridelands Red Attack 100 4 6
Forest of Thorns Green Attack 75 1 12
Divinion Fields Yellow Life 50 6 4
Ghulvania Purple Life 50 0 16
Karakoth Purple Magic 50 2 12
Wild Plains Red Attack 50 8 0
Pan's Vale Yellow Life 25 8 2
Grosh-Nak Red Attack 0 2 16
Khetar Purple Armor 0 0 20
Whitehelm Yellow Armor 0 10 0
Zhul'kari Green Attack 0 5 10