recommended size for beginners?

My two cents:

I made a MSD sized doll and that seemed a good size. It seemed big enough to me! My DD2 is bigger than her but when you make it yourself you truly get a sense of the size.

For my next project I'm making a smaller BJD character...one to work on before I make my SD-sized anthro doll I want to cast. I think personally it will be harder because it will only be 8-10 inches big (so tiny! O_o ) and getting the joints right will be hard. As for the details in a character that small, It’s really not a problem for me personally (I’ve been making tiny clay stuff for years). You just need to use a semi-firm clay (not mushy or too soft) that is not chunky or anything. I personally love Super Sculpey (Fimo and Pre`mo Sculpey are also the same professional firmness and almost the same durability/strength).