I think it all depends on whether you want hollywood-style space
fighters -- that for some obscure reason are constantly firing their
main engines anyway, and for much more obvious reasons may need to turn
quickly -- or a real-world spaceship.

A real-world spaceship will only occasionally fire /any/ engines of
notable power at all, drifting unaccelerated most of the time, with
plenty of time to change its attitude -- which is done mostly for
thermal management (attitude towards the sun), scientific reasons
(attitude towards a point of interest, though usually scientific
instruments on a manned spacecraft will have their own degrees of
freedom to track a POI), or to prepare for the occasional major course
correction. To save weight there will only be a single set of engines
for such corrections, mounted so that the array points away from the
center of mass, usually at what is perceived as the rear end of the
ship. Attitude changes will be done without haste, allowing for better
fine-tuning as well as preventing any nausea-inducing effects (any that
go significantly beyond the nausea-inducing effect of zero-g anyway).
Actual course corrections /will/ involve notable g forces, but
acceleration will be linear. No attitude changes will be made during
such acceleration burns whatsoever, except possibly to actively
stabilize the attitude(*). Any course correction procedure asking for a
deliberate change in attitude during the acceleration burn would
demonstrably be a waste of propellant.

Docking is another matter; there, attitude is mostly kept unchanged and
maneuvering thrusters are used for acceleration in arbitrary directions.
But even then, such changes will be kept minute, to both keep relative
speed low and -- again -- prevent additional nausea.

For anyone interested in real-spaceflight mechanics, Kerbal Space
Program is a highly recommended piece of software.


(* Spacecraft with continuous-thrust engines like ion drives are an
exception, but their thrust-to-weight ratio is extremely low anyway, so
there's not much acceleration going on that could potentially induce
nausea.)

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