Well my first question for old users who come back would probably be: what is the thing that you like most about this place that made you come back? and also who is favorite user that used to post here but no longer does?
For one thing, it's nice to be in a place where Democrats are red and Republicans are blue. Beyond that, despite whatever brain drain there has been over the last half-decade, this remains one of the more intelligent spaces on the Internet. If I find something interesting, other people will probably be able to say something about it, and if I have a cogent thought, presumably there'll be someone else who understands it. I appreciate that this is a place that makes it easier than most to discuss elections without having to be assaulted by other people's political opinions all the time.
As for favorite posters, the obvious (and correct answer) is Lewis Trondheim, but that's too easy. An excellent poster from long ago was Verily. I'm not sure if Boris still comes around, but over a decade ago his advice was very important to me as I grew into an adult.
I don't speak Hindi, sorry!