Devil’s Due
If this was the only episode of Star Trek I'd ever seen I'd have no interest in continuing 😅
I actually think "Inner Light" is a good option for OP because is a "side quest" that doesn't require much backstory, while still being thematically aligned with what to expect with TNG.
There is some back story needed with that one... but maybe it's tangential enough to make the viewer want to know more?