From what I have seen, a lot of people tend to go for a spouse who can also be a follower, and I have never seen the attraction of doing so. The most popular options tend to be the companions - either Ria
. If you're playing a female character and can marry one of the Companion trainers, so much the better. But there are a ton of options in the game that serve as excellent followers if you want them. In fact, if you're looking for a fighter-type follower, any of the housecarls will do as well as or better than any of the companions.
The other point is that I kind of like the income provided by having a spouse who opens a shop and makes you 100 septims a day. It's not a ton, but if you marry early in the game when money is definitely an issue, it helps. I find myself marrying one of two people in almost every game - either Ysolda
. And that's usually determined out of convenience. If I'm going to start the Dark Brotherhood quests early, it's Muiri, otherwise its Ysolda, as the latter starts putting out as soon as you bring her a mammoth tusk. Because I typically go to Halted Stream Camp early in the game, and because said camp has about 5 tusks, it's easy enough. (Also the spare tusks sell for about 70 septims each, representing a fairly good value to weight ratio in the early game.)