Do आप think I should un-fan all those people on this site who never fanned me back?

Honestly, like आप said, that's up to you. Personally, I wouldn't but, like, that's because I'm too lazy to do so and don't really see the point. I don't really unfan people unless they persistently bother me.

Frankly I've always seen fanning as less of a friend thing and और of an, 'I like the content that आप post/I share the same interests as you' type thing.

It depends on how आप look at it. If आप think of becoming someone's प्रशंसक as "friending" them, then maybe आप wouldn't want to remain their प्रशंसक if they didn't reciprocate. But others (like myself) प्रशंसक people because they like their contributions या agree with some of the टिप्पणियाँ they've made, so it doesn't matter if they don't प्रशंसक me back या even if they're no longer active here.

I personally wouldn't bother as it would take up time I don't care to use. If आप feel strongly about removing someone who didn't प्रशंसक आप back then be my guest. It doesn't matter to me in the long run. So I am in a similar नाव as Flicker.

It's up to you. I wouldn't do it as it's a waste of time and energy. I never understood the point या value of adding as a प्रशंसक here. It's not like फ्रेंड्स get extra access to privacy या something. So, I just प्रशंसक people if I have enough respect for them. And if someone adds me first, I usually add them back as an act of formality या common courtesy. The whole add as a प्रशंसक thing is nothing but a boost of ego here या sense of security/insecurity. The blocking system is somewhat useless too.