If you separate them now, there’s a chance one or both plants will suffer root damage and/or transplant shock. They seem to be thriving as they are, so I wouldn’t worry about separating them. They’re flowering, so each flower will become a cherry tomato. Try to save some of the seeds for next generation. Plant three or four pots. Try some herbs. I used to do a lot of container gardening, and still have herbs and other plants in containers.