I'm sort of thinking the populace and town guard might pretty easily hand over the gates but the palace itself would be the issue... So we'd need someone manning the walls, and then the gates open and various threads could go on with the fighting and battling?
Lily could be helping with the wounded because Kaelyn's probably going to be going Cersei-useless...
I think it would be nice to have someone NPC the captain of the kingsguard. Jaehaerys would negotiate with him.
I'd also think Matthrew v Tyrith could be hot. But that's the fangirl talking... mostly.