That's a great feeling, knowing that you built something from end to end that works!
One thing I notice that you might think about a bit...... what are you using for corks?
Kinda looks like the walmart stuff, and if it is, try experimenting with some of the rubberized corks. That was by far one of the best steps I took when I started building my own inserts. The rubberized stuff seems to hold better over the long run, and stay in tune way longer than the natural stuff.
Just a thought....
Bob