I don't think hybrid is a bad word here. Some of my favorite varieties are Sungold, Sweet Quartz, Momotaro, and Jet Star. And I've heard good things about Big Beef.
But most of us grow for flavor first and foremost, and then productivity, and barely consider getting a smooth/uniform fruit shape as a factor in variety selection.
Maybe I'm a tomato snob, but I lump Mountain Spring, Celebrity, etc. into the category of "slightly better than the grocery store".
Also, generally speaking, the best flavored tomatoes have rarely come from determinate (bush) varieties. Of course there are exceptions, and you may want to take a look at the Dwarf Project which now has over 40 varieties of flavorful tomatoes growing on 3-5 foot tall compact to semi-compact plants.
Ultimately you have to find out what your market wants, and grow the produce that will sell. If you can grow a perfectly red, round, smooth tomato with a mild flavor and sell lots of them, then who are we to judge? However there may be an untapped market of customers who would pay twice as much for tomatoes that look like this:
