A couple thoughts on alliances.
It would be great to have a “rules” page or some other standing post. It could allow leaders to specify Required donations or leave advice for new players.
Donations are too scarce and meager. 95% of my alliance, a top 5 alliance, has donated less than the amount it takes to activate the spearman. Id love to donate more, and an 8 hour cool down or 10k limit would still encourage gem buying.
Maybe each alliance could pick one up grade for free or get low level bonuses (1%unit health per alliance level) that are active no matter what.