Maybe this is sad but personally I think it'd be more useful to be able to talk to all kinds of animals than all kinds of people. Even if being able to talk to animals meant I couldn't learn another language other than English I'd be fine with that. I mean, imagining that when I'm speaking to these animals the language barrier is suddenly broken and the animals in question can all understand me perfectly and I can understand them as well and actually carry out conversations and such. That'd be pretty cool. You could use animals as spies! Covert information gatherers!