It's cool to walk in interesting places while having topics everyone's passionate to talk about.
I've been lucky to visit countries and cities by locals, so I'd love to repay the favour.
I learned to love the city, and it's never out of things to do.
My fiancée has a PhD in Paris' history, we had a lot of walks with interesting things to see or do.
I'm compiling a list of ParisRB's advice in Paris. It's on GitHub, feel free to contribute :) https://github.com/parisrb/how_tos/blob/master/paris.md
There are plenty of museums, and walks along nice streets, river banks, lesser known places, or have the historical commentary.
I won't copy/paste Que Faire à Paris ? (quefaire.paris.fr) nor Paris Secret (parissecret.fr), so the best is to get in touch and decide.