I always say to not split your focus and to focus on 1 project and finish that if that is possible.
Otherwise look that you can manage your schedule in a good amount of hours 10-12 hours.
That is how much time I invest into my goals every day.
More than 12 hours and I drop, I cannot take more projects because of the time that I have available per day.
If you have enough time per day to work on 2 projects with focus then do it.
Well, this thing here will cost me like half a day per week when we get started. And I always need ten things at the same time to juggle or I get bored. :D
I am not much of a planner, more like the spontaneous type. As soon as I write something into my calendar I don't want to do it anymore. Did I mention that I am difficult. ;)
Characters are always difficult.