No, I have not made them as single cookies, but there is definitely no reason to do so if that is what you prefer. They would just be thinner cookies.

In regard to the texture from the oatmeal: Yes they do have a different texture and flavor, but not an overwhelming oatmeal taste such as regular oatmeal cookies.

One additional comment: I realized after I had posted the recipe that there is an uncooked egg white in the frosting. Since uncooked eggs are not considered safe today, you might want to substitute a little milk for the egg white (just enough to give you the right consistency).

Let me know if I can be of further help. Hope you enjoy the cookies and Happy Baking!