Oh, Tan, the hand on the fence is very, very good.
On your rose pics, I would clone out the blemishes. My eye went right to them.
I think you'll do better with a real macro lens and sharpening. Here's what can be done with the *ist D, FA 100 macro, and nik Sharpener Pro.
http://pug.komkon.org/04jan/istdrose.html
Keep it up. You've got a good eye.
Joe