Same here, only 4 plants this year, 2 the same as yours, that Sun Gold has been a winner for me, bought it early, and if froze, but came back from the roots and 6 ft tall now, love the orange color, snack on it all day. Lemon boy does well, but fruit only 1 1/2" diameter, but tasty. Celebrity, bought twice because 1st one froze, but doing well (I grow my tomatoes in very large pots, and this one does well in pots) good flavor. Only fail, the Black Cherry, got hot and doesn't set fruit anymore. Wish I could have found a Black Prince, fantastic flavor, low acid, better for me these days, but couldn't find one. Wish I had planted a Roma, so good with pasta dishes.I would love to try what you are doing, but haven't found the time for it. I am just getting back into gardening after moving from a high elevation location.
This year I only have eight tomato plants. I planted Big Beef, Sun Gold, Sun Sugar, Roma, and Lemon Boy. I plan on saving the seeds from them for next year.