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The way I'd imagine orbital warfare working in 60YIS would be some abstracted orbit tracker where your actual orbit and the one of your opponent(s) is never 100% defined, but you know how it is relative to theirs, as that's really what matters.
For an example, you get some political mission to take out an H-Class spacecraft orbiting the moon. It's already orbiting, so maybe you roll 1d6 to see what distance its at (basically heliocentric zones but the target planet/moon is the star). You have a printed sheet that shows six 'layers' that are the zones and you place the enemy token- represented by a colored counter- on, say, the 5th layer cause you rolled a 5. You enter the Moon's SOI with a skewed orbit (probably determined by a pilot roll) that puts you on a special space that links the 6th and 3rd layer (there would need to be one for every combo). From there, it becomes turn based. It'll take you one burn (less than a map-scale burn though) to change to a 5th-to-3rd connection- since its only one difference from 6th to 5th-, however you have to wait Xd6 hours/days/months (dependent on the size of the target body) to abstract waiting for the proper time to burn. Or you could could spend double fuel plus maybe another pilot roll (or another skill, idk off the top of my head) to go directly for an intercept. From there, you- the designer- would need to determine some 'tactics doctrine' for opposing crafts as to if they want to spend their own fuel to dissolve your intercept, or try to point-defense their way through it and save on fuel. I'd imagine this would also be a table that also is used for the enemy sending orbital missiles to your ship as well. The intercepts themselves I'd imagine would be decently basic, choosing weapon(s) to shoot during the intercept- most likely determined by the robonaut(s) the ship has on hand- and damaging parts from some sort of damage table. Though of course that would require modified enemy ship sheets. Really the biggest problem this faces is added granularity for a ship that will (hopefully) be destroyed in a couple turns anyways. But I guess that could be abstracted away pretty decently, especially with those new mini-ship cards in the crewed rules.

Of course there's a million other ways this can be done, this was just one that came off the top of my head while writing this post. I think keeping it within a single sheet of paper is important since that follows the rest of the game's design philosophy- as opposed to a dedicated battle map like my wargame has- but its also important to touch on the unique tactics that are the whole reason to have this combat to this granularity in the first place. 

> attacking factories to impede production

Yeah the whole point of orbital warfare is for orbital superiority to do stuff like that, or rather stop it from happening. Orbital warfare takes a loooong time, so being able to have on-site aid is extremely important, and even more reason for the enemy to try to take that away from you. Time for some dropstones! lol