I have painted with a roller.
My advice is to make sure the roller is loaded and no air bubbles.
Apply light pressure to the roller on the tray until all bubbles have gone before you start to apply to the body.
The paint on the roller will last longer than you think and rolling one way and then again at 90 degrees helps remove deep texture.
https://youtu.be/IZL-F9Zf02Q
Looks good and I think you will get a good finish even before you cut back and polish.