Having more than one active account is in some ways a lot of trouble - you have to vote with each of them, and even if you're automating the votes it's still some work to create and maintain a strategy for it. (I guess you don't have to. But the SP in them isn't worth much otherwise.)

The main benefit is that you can separate your posts by subject so you don't stick your main audience with something they don't want. When I was doing Actifit I separated it into a different account, but they've been pushing for more content in their posts recently and it probably isn't as necessary now. This account makes more sense for Steem Monsters posts than my main, which was kind of becoming Monster-only lately. (Although this one primarily exists so that affiliate payments go to the project and not me personally.)