Freehanding is tough, to get right.
A few tips maybe, first, the shape is good, but its rough, go with thinner paint and barely touch the mini witht the tip of the brush, it may need many passages to get a good clear line. Secondly, the freehand as a whole needs to be darklined to stand out on the material, with a very thin wash to meld it in again. Once the shape is set, it should be shaded and highlighted like any part of the mini, the same goes for the white circle.
Poor freehand will only undermine your minis and focus on your weaknesses instead of your strenght, so you should master the rest before you try to do it on completed minis.
While I am at commenting, please, use a picture editing program to make montages of your minis, instead of posting multiple pics of the same subject, the voters are busy people.