New planet setting: Orbiting White Dwarf Star (tidally locked planet!)

[Call me Arty]

 A white dwarf is an interesting celestial body. The long and short of it is: A medium star (like our sun) will disperse it's energy until it's about the size of Earth. This small size means that, to have liquid water, you'd have to be almost twice as close to a White Dwarf as you would be to a medium star. As a consequence, it tidally locks the planet. This means, one side is getting all of the sunlight, one side is getting  none and is left in the cold, though there is a (potentially) habitable strip between these two extremes. This could be a pretty interesting scenario.

This isn't even adding a new system or anything overly complex, all we'd need is an adjustment to the planet generator. For one, it'd sure help exploration. Want to cross from a desert to a pole? Now you don't have to cross a planet to do so. Think you aren't getting enough interactions with other factions? Every settlement getting sandwiched between immolation and glaciation would certainly put an interesting spin on things. You might not have much reason to destroy a pirate base on a normal planet (six day trip that needs to be funded, fed, and taken care of, and that's not considering the return trip), but having enemies only a handful of tiles away might pose a more constant threat similar to insect hives.

[Tomasdav]

planet rotation is only one factor affecting overall temperature living in the dark won´t neccesserily means extremely cold condition but it would be interesting half of the planet without plants

[Bolty]

This is also true for planets in red dwarf systems. Red dwarfs are so small and so much less luminous than medium-sized stars that a habitable planet would have to orbit so close that it would almost always be tidally locked. As already mentioned by the OP, this could make for quite a challenging game mechanic, as the side of the planet in permanent daytime would be extremely hot and experience quite extreme weather. The opposite of course is then true for the night time side, as well as a lack of plants since they can't photosynthesise.

Furthermore, another interesting aspect is the brightness. Since both white dwarfs and red dwarfs are much less luminous, even the daytime side of the planet would be very dim by Earth standards. Even at midday, the brightness on a planet like this would only be about that of civil twilight on Earth. This could also be considered if something did come of this suggestion.

Solar flares can also be a problem in red dwarf systems too, so editing the frequency of solar flares in-game would also be realistic?

[Jackalvin]

Would it be possible to survive orbiting a pulsar/neutron star? Like, facing constant solar flares, and new events like solar storms that are like a near instant toxic fallout.