Yoooooo i Take back everything I said. I'm from Paris but been living in Germany for quite some time now and discovered techno here. Going alone in Paris is not so fun. Sadly, It's a big dangerous city, specially for women and the nightlife is not so friendly imo and the people don't really get it. You wanna rave alone ? Come to Germany ! Everybody gets it here and Germans are way less flirty anyways.
But maybe I'm biased since I've experienced Germany's best. Maybe Paris isn't so bad after all regarding techno and Raving. Maybe I'm just an elitist prick ! Rex club is definitely your best bet tho. Oh and definitely don't go to the club T7 ar portes de Versailles. Even if the lineup is insane and all your friends are going. It has been an organisational overfilled mess and a disappointment every single time I went there and the crowd was so bad. 2h queue each time for presales and wardrobe. Completely insane. Shittiest moneygrub ever.
Stay safe and have fun ! :)