What on earth is the science officer doing in the middle of combat? It's a very important position sure, but like the medical officer the role's duties probably begin after combat.

But honestly, look at Star Trek. Space combat is rare, the interesting stuff tends to happen on the planet (and if not it's on the ship). Even in Khan's first appearance he's on the ship and trying to take it over, not commanding his own. If space combat is important it's generally much better to make the players a fighter/mech squadron, and larger battles are generally the backdrop to a more intimate confrontation with Char or something else important to the PCs.