Not every mission has a station as a destination - quite a few will just direct you to the vicinity of a planet, and not tell you which one until you're in the system. Quite a few systems have distant binary partners with no stations out there, so they're absolutely fine for trade missions, but you can get a long trip if you pick them for e.g. surface salvage...Unless it doesn't indicate to what system you are going you can merely check the distances to the stations, if not available in the sys-map (IIRC all stations are shown before you ever visit a system and scan it) you can use EDDB.IO.
The system map will not show you the location of stations in a system you've never been to, unless it's a high-population system which comes pre-scanned.
Installations, megaships and tourist beacons are not marked on the system map, and nor are their positions catalogued in EDDB or similar. Combat zones similarly there's no guarantee that any particular system will generate them close to the primary star (though most do).
A few mission types have you go to system A (mentioned in the mission) where a contact will then tell you to go to system B (could be anywhere within 20 LY), so good luck assessing those in advance.
Yes, if you're extremely cautious and avoid several mission types entirely, you can avoid having to travel long supercruise distances. But that's very much a workaround for the problem.