Single Player Siege Maps. A.I. Reinforcements

I'm sure this has been brought up before but I'm going to suggest it.

I've been having the thought lately of instead of just time based goblin maps, have resource based "siege" maps, which would progressively get harder similar to goblin maps.

The idea is, having big maps that instead of being timed, you go into a siege with your allowed camp size and a percentage of your elixir/dark elixir (based on the amount in your storages).

The reasoning for the resource based maps is since the maps are so big you wouldn't have time for a 100% victory in 3 minutes, so instead you have a set of barracks' (same levels as in your normal base) on the actual siege map so you could create fresh troops during the siege!

The barracks' would be pre placed for each map. (Instead of ocean or beachfront have attack camp decoration along with barracks'.)

The reasoning behind needing so many troops is that each map has a set amount of reinforcements inside the city that spawn out of those little goblin huts (similar to cc spawn).

Reinforcements: siege defenders would start at low levels through the first few maps then progressively get to higher levels the further along you go.

Victory/Loss conditions:
You win once you have taken over 50% of the city or more.
You lose if all your troops are killed or you run out of resources.

Loot: Each map would have a set resource cap (similar to goblin maps) except your loot percentage or loot earned would be based on percentage of the city you destroy/occupy.

Just an idea that I think would really enhance the game, if not enhance at least be something new to try.
This might already be ruled out but I couldn't find it if so.

Thanks.