For your third figure you some great work. Salvatore.
Some comments; I wonder what is the color that you do the shading. It seems that you use black. Stay away from black and use the complementary color for shading.
Then the paint looks glossy. I'm a oilpainter to, and i would recommend the following tricks to avoid glossy paint.
Put a blob of paint on a indexcard or something similar. Let it stay there for about 15 minutes. Then you see that the oil is soaked out of the paint. Remove the paint from the card and bring it to your pallet. With some White Spirit (very little) you can made the paint fluidable and paint the figure.
After a painting session I put the figure into a drybox (wooden box with a lightbulb 65 W). I let it stay overnight. The next morning it isn't shiny and dry.
Marc