In this post here are my thoughts about removing a seat, which is a prime structural member.
https://forum.tinboats.net/viewtopic.php?f=21&t=38511
That said, you clearly have capabilities and resources at your disposal, so I'm sure you could add some simple bracing to help reinforce that area. And with a 12' skiff, you're not going to be plowing into waves like I imagine larger hulls would, and from where my concern lies.
You did a nice & clean job one those transom corners!