Note that the ice breaker tours start running on or about January 20.

For the choices you listed, there are a few things to consider. The Drift Ice Museum will present much the same information as the cruise - only inside a warm building. They have a movie-lecture theater that shows some beautiful images and videos from the trips and other research activities. They also have a small display area of photos and samples and a "cold room" in which you can experience drift-type ice in controlled conditions. The point is that it might be a bit redundant if you also take the real tour. In addition to the nice museum, the grounds have several points that give nice views out over the bay, with the Shiretoko Peninsula in the background - assuming they are not fogged in.

The prison display is mostly outdoors and constitutes a rather lengthy, self-guided walking tour. I spent hours there in the fall, happily taking photos. In January, it will probably be pretty cold so decide accordingly. I found it fascinating but I was there in shirt-sleeve weather.

I didn't see the Northern Peoples Museum in Abashiri because I spent a fair amount of time at the ones in Hakodate and Sapporo. I would recommend one or two of them but you don't really need to see them all unless you are really interested in the Ainu and their near-by relatives.