Condition is the big item for marble value. Even a tiny chip can decease value by half or more. So, with cat's-eyes, they pretty much need to be mint to have value. The larger ones (of same type) would generally be worth more than the smaller ones. I don't have a percentage increase. As far as types, in the foreign ones, the cross-through types where instead of 3 different color pairs of vanes (side-by-side), you have the 3 different colors across from each other. I'll post a picture. Also, the Vitro style cat's-eyes, which I don't think I have seen in your picturs yet, are sometimes more valuable when they are hybrids - meaning 2 or 3 colors in the same vane. I'll post a picture of those, too. So, that's a beginning of an answer.