While I think the idea of a figure eight orbit, or other powered orbit, maintaining an overhead relation to a landing party makes sense, I'm unaware that this is what was intended. We hear about "standard orbits", which really implies something elliptical. But we don't really hear any details about how the ship maneuvers in orbit, beyond the hand-wavy (and far-fetched) need to maintain power lest the ship spiral down to the planet in a matter of minutes.
your idea makes sense, but based on the evidence it would be a flat out retcon, I believe. Any descent into the atmosphere can be avoided by a powered ascent to a circular orbit which should remain stable for days, weeks, months, or longer, depending on the altitude. If the orbit is decaying rapidly due to atmospheric drag, then the ship would be heating up and the hull ablating. That never happened. If it's decaying rapidly
due to a lot of moons in the area, then I really doubt that system would be stable enough to last very long, and at least one of the moons should be disintegrating into a ring system, and the ship shouldn't be in low orbit anyway. And so forth.
The determining factors have always favored something that on the surface sounds plausible enough (to stay in genre), but which doesn't have any scientific depth (sparing the viewers from science lectures), and otherwise whose attributes serve the drama (because milking things for dramatic effect is what keeps viewers tuning in).