This I think is your best picture though it is a bit blurry at the nib end. I would say you have the slims mastered! I don't care for the fat look on any pen style, having said that, your grain lines up nicely and you appear to have a nice meeting between the wood and nib. Would you believe I can't think of a better way to say it right now!! Sometimes the angle of pics make it hard to see if the wood has been over/under turned, this looks to be just right.
On one of your slims you have made a protrusion and then a straight edge at underneath. I am wondering how this would feel to hold and if it would be comfortable. You may be just trying out designs, I don't know. If not, I think it would be awkward to hold.