Hi Jeff: You did not ask for suggestions or comments, but I will give some absolutely FREE of charge!!!
Your pictures are HUGE!!! Maybe a little smaller...
Pen #1: The wood, the segmenting, the materials - GREAT! My only thought would be to have the top and bottom segmenting the same (i.e. Scallops - both top and bottom; or straight segments - both top and bottom). What you did is excellent, so this is just a thought to consider.
Superb Segmenting Jeff,
Great Selection of Materials, Very Precise Alignment of Elements.
Excellent Fit and Finish.
Outstanding Craftsmanship.
Congratulations,
Brian.