SP Defence Map, need ideas!

[Hadhafang]

I'm currently making a campaign.. the first map is a map in which your hero helps a CPU player to defend a town.. The town has 3 buildings all of which the enemy will attack but the map lasts for 25 minutes and I need some things to make it more enjoyable.

Features so far:

- Basic Attack Waves from 2-3 different entrances
- Small, frequent attack waves from 2-3 different entrances
- Boss waves, an enemy hero + stronger mobs attack a building
- 'Ambush Waves' - Enemies appear within the town to attack
- Hero Revival System
- Item shop

Currently, the only unit the player controls is their hero and the camera is locked to them, the computer player controls all defending units who are pre-placed units.

Does anybody have any good ideas of things to add to make the map for enjoyable?

 

[supertoinkz]

when a unit dies, it drops it's weapon. your hero has a basic sword as starting weapon
so when he\she picks the weapons, it will be attached :3
you can buy horses to travel faste
use guns and arrows
oops, its a town xD

 

[Hadhafang]

lol.. yeah, theres 3 different buildings that you can enter and leave, they all get attacked and you have to prevent the leader in the final building from being killed.