The conquest and spaceship players are playing different games, so an equal handicap is not necessary, however in the spirit of adding difficulty, how about adding a requirement that spaceship players acquire an atrocious reputation by the 1AD save?
This should make it more difficult to get the techs for an early landing.
As it is now, 2.42 players have an advantage of a more reasonable AI, and I might just try MGE for spotless conquest.