Change leaderboards so they add up and display leaders for each Kingdom instead of overall, by points earned when that kingdom was set to Home. Make rewards for being ON the leaderboard go deeper, starting with perhaps the top half.
This would help to spread people out, so everyone isn’t just in Whitehelm, AND would give many more players the ability to gain, and display, #1 rankings and get more of the rewards for said rankings.
Top kingdom goes to whitehelm. Lowest kingdom goes to broken spire. (prediction)
Whitehelm is currently highest gain as economy favors glory still but i do like your suggestion nevertheless.
I’m generally in favor of making home kingdom matter for something more than just maximizing tribute reward, which generally pushes everyone towards Whitehelm. Multi-tier leaderboards have been suggested, and I believe rejected, in the past, but this could be a novel way to spread people out. Having guilds compete for kingdoms might be interesting. A guild may decide to consolidate on one kingdom, or spread out over multiple kingdoms, if they feel strong enough.