Well, we clearly have artificial gravity in our little techno-continuity; acceleration alone wouldn't account under all circumstances for Polaris's
internal environment as we see it.
In building Saladin
I've tried to detail it so as to suggest that gravity runs along different axes in different modules of the ship, giving us more wiggle room for interpretation on various vessels.
Rather than ask artists to constrain themselves to a particular approach, what I've come to is that there are issues of how systems "scale" on our ships.
For example, little Polaris
has some nifty variable-geometry sails to manage parts of its FTL drive in an energy-efficient manner,while a behemoth like Saladin
employs huge fixed structures that draw on enormous energy resources and "brute force."
The real reason for the design difference is that if we put structures on Saladin
that both move quickly enough and are proportionately large enough to be seen in quick-cut shots I'm afraid it'll appear less massive and we'll destroy the sense of scale difference between it and Polaris
So, on the matter of gravity - it's more practical and efficient for a small vessel like Polaris
to make use of acceleration forces to help with the gravity situation, but much bigger ships can prioritize other design demands over efficiency because they have enough energy resources not to have to worry about it.
Or something. Sometimes forward is up and sometimes it's not.