One of the things I've noticed is that outer-space battles tend to get rather large and unwieldy when done on a minifig scale, making it difficult for smaller collections to manage. I haven't tested this concept yet, but I've made some little extra rules and ideas allowing considerable larger battles in space by simply working on micro scale.
Part 1: Fighters
A fighter is a small ship, with just enough room inside for a minifig to pilot (though you could leave some dangling on the wings). They have the following stats:
The observant will notice that these are the EXACT SAME stats of a minifig wielding a pistol. Since we're working on a different scale, we can get away with that. I'll explain boardability in a little bit.
The Upgraded Fighter
By nearly doubling the cost, your pilots can have even better ships. If you haven't noticed, this is pretty much the Hero with a rifle. Stats are the only similarity though: Upgraded fighters do not have Egos, nor can they perform Stupendous deeds.
Part 2: The Carrier
The Carrier, based off the noble Horse, is used for moving fighters about faster. They are considered to be piloted,making them intelligent: however, they can also be commandeered (more on that later), unlike fighters.They have no weapons, so they may want an escort. They have two pilots inside to move it about.
A Carrier can carry up to two fighters at a time. If both slots are filled, enemies will find it difficult to board.
Part 3: The Frigate
Weapon: Cannon (X2)
The Frigate is basically the Carrier, only bigger. They can carry up to four Fighters, or two Carriers, or a Carrier and two Fighters. They also have room for a crew of 6, including passengers.
Part 4: Boarding
Yes! It's possible to board Carriers and Frigates. A few notes though:
Is there room to land? If not, you can't board the ship. Fighters can not be boarded, though they can be commandeered.
The people inside ships are always considered pilots, in the event of hand to hand combat.
To represent the insides of ships, build them up on baseplates, or mark off areas with tape. These are the insides, where minifigs can fight. Be sure to be VERY clear as to where one should enter when boarding, and where the controls are. Put your crew on here.
If there are no living opposing units in a ship, a pilot takes it over when sufficient crew are ready (Two for carriers, four for frigates).
Taking fighters works the same way, only the fighter must be parked and the pilot must exit it before engaging in combat. IF they die in the cock pit, they will need to be dumped out by an enemy.
Hmmm..... Am I forgetting anything?