In Japan I tried Mizuho which is called "The Queen of Loquats".
It's bigger than an apricot, roughly 3-4" in diameter when thinned to the standard one per branch.
It's a yellow type, in between the white and orange, strongly leaning toward white.
It's very sweet, but I feel that there must be loquats out there with unique flavors, and this one has a fairly standard profile with high sweetness.
It has a rather large seed cavity with anywhere from 8-11 seeds.
If size is the end-all, be-all, then many varieties would fit the bill, when strict thinning is applied.
Most people who have tried 'Chinadoll' have a strong preference for it.