So, if you had a story set in an inhabited Solar System - where there were human settlements all the way from the Vulcanoids to Sedna - and there was a steady cargo and passenger traffic between Mercury and Venus and Earth and Mars and Ganymede and Titan and Titania and the Kuiper belt - and you were using, say, some kind of sublight reactionless drive so you were working with Age of Sail-level travel times and minimal weird shit in the physics - would there be, for lack of a better term, "trade routes"?

That is, assuming each ship is taking the quickest ballistic course from one planet to the next nearest, would a steady stream of takeoffs produce a continuous-ish curve of ships moving through space, or would it be sensitive enough to initial conditions that you'd get ships scattered all through the areas around the ecliptic? Or would it make no sense to have a steady stream of takeoffs in the first place, even with fast reactionless drives, rather than riding the planets until they're closer?

I feel like this is something SF should have answered for me already but I'm not actually remembering anything that deals with it in hard-SF detail. Probably because orbits are hard.

Instinct says you would get a "trade route" - one that was wildly curvy and swung around a lot relative to the ecliptic, and where the planets weren't always visited in the same order, and maybe discontinuous around oppositions and conjunctions, but where you could trace long lines of ships if you were looking down on the system from above.

Instinct also tells me my instinct is usually wrong when it comes to thinking about orbits.

Instinct also tells me that trying to working it out from the basic physics would take me down a long rabbit-hole. As would downloading Kerbal Space Program or some other launch simulator.