We have a pretty good idea of what attributes a planet would need to sustain life and one can imagine how life might develop on a planet, even in difficult environments.
I find it extremely difficult to imagine what a habitable natural satellite would most probably look like.
While it is pleasing to think of the forest moon of Endor or that of Avatar, those moons are pretty much planets as far as what the environment looks like.
Apparently, tidally locked moons might have a chance to regulate temperature more easily through plate tectonics, but I believe it also means only one side of the moon is directed towards the sun and the other always faces towards the primary. How would vegetation spread this way? If liquid water forms on one side, it most probably could not on the other side.
Would it be more likely to have tidally locked moon develop life or rather the contrary?
Would a habitable moon also possess poles the same way the earth does?
How likely is it that a moon possesses a stable atmosphere?
What would be the effect of gravity on climate and life?
Or the effect of the rotation around the primary?
What conditions on the orbit and on the primary would prevent extreme variations in temperature?
Could a habitable moon have seasons? Would those seasons most probably vary in length? Would their occurrences follow a foreseeable pattern?
I know this is a complex matter, which might be seen as "too broad", but I very specifically look for basic ground rules to create believable habitable moons. Any idea, insight, or link to a study would be appreciated.