[AlexanderHowl]

One possibility for a tide-locked planet that is not often talked about is a planet with a 90-degree axis that 'rolls' as it revolves around its star (the north pole is always pointed at the star, the south pole is always pointed away, and the equator is the terminus). In recent reports though, there are some rather massive differences in temperature between the night side and dark side of directly observed tide-locked planets with very dense atmospheres. I am not sure if the mathematical models of previous research actually reflect reality.

For example, there is a planet where molten iron replaces water, and it possesses a day side with temperatures 150% higher than the night side. The molten iron vaporizes in the dayside, rains down at the terminus, and freezes on the night side. Of course, iron gas is much less reflective than water vapor, so that would drive up the day side temperatures, but it is an amazing planet.

Another thing to consider is the placement of continents. A 'polar' ocean would moderate day side temperatures through evaporation and reflective cloud cover, as well as being an effective method of transferring heat to the night side. Conversely, a 'polar' continent would be an inferno, and the rest of the planet would likely be uninhabitable outside of the terminus because there would be insufficient heat transfer. Of course, the tidal bulge caused by the tide locking would likely result in a polar continent, meaning that most tide-locked planets are likely uninhabitable outside of the terminus.