We replicated a “Shed” with almost the same footprint some years ago for the Canterbury Shaker Village. In that instance the framing was based on existing photographs and the others buildings in the village.
The structural ridge suggests you are not holding yourself to such constraints, and are free to do anything you wish.
All the same I would drop it. (That though may be personal bias, I hate them) It this instance it limits use of the attic space greatly.
I'd raise the ties a little, and join principal rafters to them , a principal purlin to that, full length cogged over it in a higher plane, with the common rafters cogged over it, and the roof plane in yet another layer.
Unless the girt height is situated to accommodate a tractor I'd drop it a little, and I would again go with layered systems. Cogging the joists over the girts, and raising the connecting girts to the same height, thusly eliminating the three and two way connection in the posts.
Structural elements needn't line up, particularly in an out-building. A frame is often all the better structurally and more pleasing to the eye, when they don't.
Use the frame as a teaching exercise for yourself, and play a little.