After looking at the other microspace systems, and deeming them all too complex to remember (and too long to bother to read) I decided to make a simple system, following the original Brikwars rules as much as possible. In fact there are only three rule changes in my system.
1. Pivoting
Ships with a Size of 2 or more can pivot 45 degrees per turn. Smaller ships can pivot freely.
2. Weapons
Weapons on micro ships are small. Guns that are facing the same direction can be counted as a single gun whose Size is the combined Size of its components. Ships carrying fighters or boarding shuttles counts them as a melee weapon.
3. Armor
The Structure Level of a ship must be smaller than its Size. For comparison, a ship with SL 0 is lightly constructed and has no shields (example: X-Wing) while a ship with SL 5 is very sturdily built and heavily shielded (example: Death Star).