Great game!
I got 1000 points using:
Wizard +9 health +9 magic +3 chain in center back (podium)
Healer +9 health +8 healing +3 range 2 squares to the side of the wizard
Healer no upgrades 2 squares to the other side of the wizard
You can beat it with a lot of setups I'm sure, but this worked for me. Watch your health and don't lose any troops!