When John Spencer died, the cast of The West Wing
filmed an intro for the first episode to air after his death, to honor his memory. And then killed off his character on the show in a way similiar to how Spencer himself had died.
Not sayin' that the same thing has to be done here, of course, since the show wasn't titled "The Leo McGarry Hour" or anything.
And I'm really not that big a fan of SJA, its aimed too much at kids for my tastes. But for fans who would like to see the idea of the series - a former companion workin' with teens to keep the world safe, Jo would be the best bet.