We'll Find Out Baby Yoda's True Origins
In the season one finale, Din Djarin is formally charged with the care of Baby Yoda, which includes a pledge to attempt to take him to his real home. "By creed it is in your care . . . You have no choice, you must reunite it with its own kind," the Mandalorian Armorer reminds Din. This seems like a pretty obvious hint that season two will, at least in part, revolve around the Mandalorian attempting to fulfil this promise by searching for the Child's true origins.
Of course, that's easier said than done. Yoda's species is famously mysterious, and very little is known about them in-universe or in fan lore. We don't even know the Child's real name, hence the "Baby Yoda" nickname! In some ways, that's parallel to the Mandalorian in season one: identified more by origin than by real name until the season finale, so perhaps the same thing will happen in season two with Baby Yoda!
There's a catch to this, though — the Armorer's line about Baby Yoda's "own kind" is part of a larger discussion not about the child's species, but about the Jedi Order. If that's the case, then it opens even more doors: at this point in the Star Wars timeline (soon after the original trilogy ended and the Empire fell), we've always assumed the last known Jedi is Luke Skywalker — could there be more in hiding all this time? Have some of the Rebels characters (such as Ahsoka Tano) have survived? These questions could easily be at the centre of The Mandalorian's second season.