I'm thinking that Moscow, with all of its challenges and chaos, probably deserves a bit more attention than St. Petersburg. At least I see it that way. Plus, I have researched Moscow a bit more over the years and would regret not seeing and doing as much as possible. St. Petersburg, on the other hand, is going to be lovely, yet the city is well-designed for walking, which means we probably won't wear ourselves out as much.
Let me also add that we are much more interested in exploring streets and seeing how everyday people get about. I like unique things, so boat rides on the river, visiting a farmer's market, seeing a Stalin exhibition, and taking a Russian bath truly interest me. I am also not keen on devoting lots of time to touring monasteries and churches. For me, it would get boring rather quickly. I'd love to see the exterior of any building, but not necessarily tour the place or grounds for hours. I'm much more interested in drinking a cappuccino near some beautiful building.
I prefer secular Russia over religious. I also have a strong interest in anything WWII. In addition, I don't want to be worn out from feeling we must overdo it. Therefore, we're willing to do tourist stuff half the day and relaxing stuff the other half. And, we might just book a tour or two to make life easier. Last but not least, we are fairly budget minded, but not to the point of missing out on some musts. - from an e-mail to an American contact in Moscow who was assisting me.
I had thought long and hard about visiting Volgograd (formerly Stalingrad), but airfare rates in Moscow were exorbitantly high. Plus, we were facing a time crunch. The big area I had marked to the east of Moscow is The Golden Ring. We also were not able to tour it, mainly due to a lack of time. The longer I travel, the more time I feel I need to explore cities, regions and certainly countries. No longer do quick stops really satisfy me.