So, What Languages?

The next step is to pick my list of languages to learn. Keeping in mind that I need to pick 10 languages from four families turns out to be much harder than I thought. I didn't know so many languages were in the Indo-European family. Just look at the list from Wikipedia. Who knew that Punjabi and German were considered part of the same language family?? I mean, I knew they all descended from PIE but I didn't know that they were still considered part of the same family.

I've decided on Chinese and Arabic for sure. So, there are 8 slots left. I'd like to get a Slavic language in like Russian. But that's an IE language and I need to be sure of it before I definitely commit to it.

I'd love to get some suggestions from people as to what might go on the list and why. Anyone?