"German had a sort of negative connotation"
I can unfortunately imagine why. I have two Israeli friends and one of them (and hence their kids) have a German passport - and still her father refused to even change planes in Germany for decades [I think he, too, has finally kind of sort of made peace].

I'm not sure whether my kids will get more intelligent, but the part about speaking with more people is the angle I aim for. I've been fascinated by foreign languages since I was a small child, precisely because I couldn't stand the idea of there being people I couldn't talk to.