Some ideas: raiding, seiging, spell AI and more..

[Soapyfrog]

If everyone hoards then "great". However NOT hoarding is not a viable strategy. That's bad.

You might maybe get away with it on a small, crowded map... games that don't Last much past (or get called at) 40-50 turns will probably not see hoarding as a serious problem.

Large maps are fun becuase they are large, there is more opportunity for give and take, the game is more epic, more sweeping. But it loses most of it's allure as you are forced into a few narrowly defined strategies revolving around hoarding. So as you can see the things I find fun about large maps are mostly cancelled out by the devolution of the game caused by hoarding strategies.

It's like any game that has a shortcoming. You fix that shortcoming and you have a better game. It's not complicated.