Here's a rough kernel test for the 'rings'. This should be quite workable in a real game if everything is flickered at 30Hz (player ship, one shot, enemy fireball, and two chaser mines). Hold player 1 fire to slow down the animation; hold player 2 fire to disable the shift-in data. Color/BW toggles 30Hz flicker. The funny 8x8 block in the middle would be the enemy space ship, which could be drawn at 1lk or 2lk resolution. The plan is probably for rings to have 32 or 48 segments which would be in groups of 3 or so, possibly with some small gaps so that even a full 'ring' would seem to rotate.
The kernel code is horrible and bloated, but should be good as a feasibility test.