Kiev is probably not a good city to go to if you want to learn Russian. Ukrainian is used a lot there, I found it really confusing.
Depending on your lifestyle in the USA, be prepared for a very different situation in Russia.
Also, you probably need to know a bit of Russian before you go. If you don't, you need to start studying.

The issue of possible racism in Russia has come up quite a bit. It seems that the people who are occassionally (very rarely) targetted for attacks are poor immigrants from Central Asia. Lots of black (and non-white) people have been on this forum and said they had no problem at all in Moscow and St Petersburg. You can probably avoid risky situations by avoiding bad areas late at night.
Russia, has citizens of many different ethnic compositions as far as I know.
It's a cool and exciting idea, hope you go through with it!