Now that I think about it, the 'warring castles' style should definitely go in.
I think I'll make levels that are divided down the middle - you are unable to control or 'hold' objects in the 'dark side' of the level ( where the monsters have their own little fortress of blocks ), and they troop out toward you. You can only throw things into their side, or set up weaponry to fire into it - and the level should be wide enough that it is tough to aim properly. And of course, once you throw something over there, you can't recover it to re-throw.
I like it.
Other short-list stuff I need to add -
*rubber blocks - bounce back objects that strike them ( probably triangular )
*'swallowing' monsters that suck down objects thrown at them from the front and spit them back
*zombies on at least a few of the graveyard levels
*crazy chickens - If damaged, countdown and explode, but very fast producers
*Magician monsters that throw fireballs you can't grab
*Magnet object to auto-gather eggs in a region
*Cows. Something has to throw cows. I don't really care what.
*Treasure chests - feverishly tap them to open for a sudden blast of gold ( unless they are a mimic and spawn monsters? )
UI stuff -
*Need hold-descriptions on items in item loadout
*Some better ingame tutorial stuff.
*POW BIFF SMACK style popups when you hit monsters. Color and scale correspond to potency of the hit.
Other Minigame ideas
*Bridge builder - must build a bridge over a valley and have a siege tower successfully reach the other side.
*Chicken skee-ball. Use a swing-arm on a pivot that you drag up and let go to 'kick' them down the ramp.
*Monster convoy - must bomb and destroy X percent of the convoy
*Tornado level - must save chickens before they blow away - strong horizontal gravity, have to set up blockers to keep chickens in. Debris blows in and shatters the defenses you set up.