Well, a season would probably be two long. Maybe fifteen episodes. I could see them wanting to fuse together, (either by experimentation, or a romantic relationship) and Opal being a character for a healthy amount of episodes, and embracing her now long held existence, but I would think that she would feel lonesome, or feel always being surrounded, since some fusions either never feel alone (Garnet's case) or feel like they're always alone (Stevonnie's case) and a co-plot could be Steven loving Opal, but eventually missing Garnet and Pearl, then they decide to separate. Not for Steven's sake, but more likely for their own sake. I would SOOOOOO love to see Opal's character development even if it's over a short time frame.