Same question I have wondered about actual bullets from makers. Small samplers like dishes at a restaurant. Why can't you load 100, 250, or 500 at certain COAL, 500 at another COAL, then switch powder charge weights, then switch powders, then switch bullets, etc. That way you have your measurements set for 100, 250 or 500 rounds. Seating depth, charge weight, bullet style, etc.
What ever change you make, load another "run", then make another change. Sooner or later you will say enough, stop, and for example if you are loading in runs/groups of 250 and make ten (10) changes then you would have a total of 2500 rounds, then sell them in sample packs of 100, with 10 samples of 10 each.
For people who wanted 50 Hornady or 50 Sierra, sell them in smaller units but with a premium. Take them out of your original batch.
Start with a limit of 10 most reloaded cartridges. 223. 22/250, 243, 260, 6.5, 270, 7mm/08, 308, 30-06, 300 wm, 7mm mag, etc. Some for hunting, some for long range, some for suppressed.
Face the facts, one of the pleasures of reloading is the ultimate round. But when you consider all the factors involved, it is almost impossible for a reloader to say they have tested every possible factor for just one cartridge. Too many variables, like winning the lotto...
One of the reason I finally settled down to 308 bullets was the convenience of maker, bullet, style, weight, etc. At least I could try them in a variety of calibers.