The system I suggested was a generic one that could be made in any system.

Also, prepare for some serious vector maths with your barrel roll method!!

Good news with your position system too, I got around that problem by using some of the features of lists in Python (len, sort etc) that do not rely on fixed variables.

A question: how are you handling collisions? Are you using linear velocity or straight collision detection (e.g. a bump from a ship = - 5 health)?