Dreps,
You may be right about the dress code.
We did this on Oceania (also 3 days in St. Petersburg). I know you will love this cruise and St. Petersburg in particular.
stoli69 - the private tours are better as you have choices of where you want to go, how much time you want to spend, etc.
Of course, if your tours on Regent will be free, that would be hard to beat. You can do search on CC for tours but Alla's, Red October come to mind. Alla is fantastic.
As far as Moscow - I'd stick to St. Petersburg. There is more than enough to see/do for 3 days and you won't see much of Moscow (also a very, very long day and expensive trip).
JMO

I believe Regent has less "dress up" nights because of the more upscale and sophisticated clientel. Even on an informal night, nobeody is going to show up in shorts and a tank top. As another poster said, many will wear a jacket no matter what the dress code. It's the same with the free liquor all through the cruise. Despite being able to get a drink anywhere on the ship and even stock a bar in your cabin, a can't recall ever seeing someone really drunk. I always hear horror stories of out-of-control drunks on other cruises, even though drinks are four or five bucks. It's all in who you're sailing with.

Hello everyone

My husband and I are taking an all inclusive Regent cruise to the baltic at the end of July. We are trying to decide whether to sign up for their free excursion tours or hire our own tour guide in st Petersburg? Does it pay for us to get a visa to do St Petersburg at our own pace? We have 3 days.
Does anyone know if the ship docks within walking distance of the center of town?
Nana541, you said that your husband wore tennis collared shirts, most nights. Do you mean polo shirts? My husband would love this. Thank you

I think you would get better (more accurate and faster) answers on Regent's CC (CruiseCritic) board; or you can even do a search there.