[FT4] Full Thrust for Four-year-olds

My older son turned 4 today and he's going to hold me to a promise I 
made him to teach him my "spaceship game". I'm looking for advice on 
simplifying FT to a 2 ship (to start) game that wont' overwhelm or bore 
him. I know some listers have experience in this regime and would 
appreciate any advice.

He's already decided his ship will be my SDN, mine will be my CVH, and 
his 21 month old brother's will be a nice heavy cruiser. I think little 
bro will wait a while before I let his brother try to blow him up.

Noam R. Izenberg