Here are my suggestions:
After 48 hours inactive domium change his colour from red to gray, after this change players have possibility to take this land with all structures, but player who want take somebody inactive land must have domium on this same level or bigger, if he have bigger domium and take somebody land, he need to again collect materials to increase new territory. Possibility to take somebody land is active for 24 hours, after this time inactive domium disappear.
Treasures appear in random places on map every 1 hour, in treasures players can find some food, seeds, parts of leather clothes, formulas, 20 % chance to find iron tool, 5 % to find steel tool (Currently treasures respawn in this same places and to often, players can find iron and steel parts of clothes, almost in every chest are iron tool, its too easy to dress up in iron or steel set)
- Sets, weapons:
Steel set should give most protection from all sets, steel weapon should do most damage( Currently some tools do more damage then swords of this same type), shields should give some chance to block attacks from arrows or weapons another players,
for example - i have iron shield i got 25 % to block somebody attack.
- Siege weapons, walls, gates:
Battering ram - reduction time to use from 8 hours to 6 ( Battering ram is easier to detect, that why I think this should have smaller waiting time)
Walls, doors - Possibility to destroy walls or doors equal or less quality to our weapons,
for example - I have steel sword i can destroy iron doors with 3000 attacks, when i have iron sword i can destroy iron doors with 4500 attacks.
Possibility to destroy palisade gate with iron or steel weapon (Today i attacked palisade gate 3400 times using steel sword and gate wasnt even damaged)
Stone walls, brick walls, iron gates, steel gates should be can to destroy only with Battering ram or ballista.
These are mix of my and my friend Aliezov ideas.