I went there three years ago. I'm a huge fan of russian history especially the revolution and soviet era. Stayed in Moscow only and visited the lenin mausoleum which was

If only that fool kruschev hadn't removed stalin's body I would've seen the vozhd himself.
I had an awesome time. I was with two friends who were cacs so I'm not sure how it would've been if I was by myself, But I saw lots of Africans and surprisingly quite a bit of half black half russian people.
I spoke to the Africans about racism and yes they said it was pretty bad and they usually travel in packs but they also said it's mostly at night when some of the young dudes are drunk and shout racist abuse at them, but they just ignore it as fighting back isn't advisable.(they simply don't have the numbers)
Personally, I went out every night to bars and clubs and didn't face any racism. Most of the dudes were really interested in us and asked me questions about where I was from and I also chopped it up with the old folks asking them questions about their experiences during the stalin era.
I would say if you're not into russian history, it's really not worth it.