The True Answer: A LOT OF THINGS!
The first thing that springs to mind is as someone already mentioned a dynamic bank using campaign like the Rexxar one (At least I've never seen one that
truly uses it's capabilities).
Would be awesome if someone creates A REAL TURNED based multiplayer like Heroes of Might and Magic map for wc3.
Saw your sig... I actually did attempt a turn based map, I used to love playing TBS/Hot seat (one pc multiplayer) games with my friends, so I started work on something.
It was a European map and you had 'armies' that you could move so much per turn, and each army consisted of up to 100 units, out of swordsman/archers etc
When you attacked an enemy army, the battle was auto-fought on a separate 'battlefield' map (obviously unfair to let one player control his men).
I probably still have the file somewhere, I won't lie it wasn't amazing and far from finished but making a 'tbs' system is far from hard
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One thing I obviously didn't attempt was the turn based battles, like in heroes/might magic, it was just ai-real-time.
But it would be the same principle!
And yeah I to would like to see this =)