i start this thread to collect good ideas or even playtested mods. links to additional homemade material could be collected here.
here are my first themes i will go to work on
double sized runewars for up to 8 players with 8 races
6 hexagon homerealms
npc homerealms who are not played active but full of enemy units and worth to raid it.
characters going to the monsters to fight, persuade or enchant them, not the troops doing that anymore
characters joining the armies and battles
alternative vixtory conditions
a pregame where players start with a character in one of the neutral cities, quest and develop in runebound-talisman style until they are strong enoough to go to the homelands and finally to the castles within the homerealms, maybe a descent or dungeonquest scenery to get a royal artifact like the crown of command which enables them to start the original runewars game and gives the owner an advantage to the second part of the game.
trade and diplomacy within the aligned races, more resources
more monsters, using descent models, moving monsters
more units, probably using gamesworkshop or battlelore units.