semi-inertial tactical movement

    This is based on the view of wildspace as physically virtualy empty, but
with a magical medium against which the helm can push to provide motive
force.
So, I was thinking that if we keep track of the ship's speed each turn, and
add half this to the ship's SR next turn, due to magical friction (iff there
is an operating helm on board) plus physical inertia.  But, the helm has a
maximum attainable speed based in part on the helmsman in addition to its
maximum thrust (which in this system should be lower than before
(friction)).
    i.e. a minor helm does 1/5th and a major 1/3rd of helmsman's class
levels in thrust.
    ex. an 8th level wizard with a major helm is at rest. Rnd 1:  at full
thrust the ship moves 2 spaces. Rnd 2:  the ship's inertia moves it one
space, and the helm adds another 2 SR, for a total of three spaces this
turn.  etc.
--
Secondly, how about having manuverability ratings as how many SR points can
be turned from striaght ahead, how angled off and how spun the ship can be
at end of turn, each round, with the motive force of the helm being
naturally forward thrust.
MC:A  8 points* 90deg., max 180deg.; turn 180deg.
             i.e. SR 8 sidesaddle lurch
                    OR at SR 4 stop dead
                and turn around in one turn (even if still gliding
backwards)
B  6 points*90deg., max 180 deg.; turn 90deg.
        i.e. two turns to turn around
C  4 points*90 deg., max 90 deg.; turn 90deg.
       ex. going at speed 4 with SR 2 helm. right angle turn, thrust  turned
to oppose previous motion, other 2 speed points turned to right angle.  Ship
moved 2 spaces to the side, 0 forward, and is facing to the side.
D  4 points*45deg., max 90deg.; turn 45deg.
E  2 points*45deg., max 90deg.;turn 45 deg.
F  2 points*45deg., max 45deg.; turn 45 deg.
G  1 point*45deg., max 45deg.; turn 50% chance 45deg.