Great Job!
That looks really good. The rawhide edging is such an incredible improvement over the garden hose the SCA used as a standard for so many years.
I have only made sheilds for SCA combat, but I have made a lot of round shields. Take my advice for what it's worth.
I don't make my bosses. I buy them. It seems better to let others who are really good at it do it. I am no good at making them. Sixteen guage dents up, but it is a lot lighter than fourteen guage.
1/2" is a little heavy, but with a sheild that size, you wont have many problems. You look like you are a pretty big, strong guy, so I wouldn't worry about it. I use 1/2". Most folks like 3/8".
I really, really like the paint job.
You didn't do three things that I do.
This isn't a criticism. Your sheild looks better than about 90% of the sheilds I saw at pennsic. Truly a cool sheild.
The first thing that you might consider doing on the next one is to cover the front with some cloth (I use cotton) and some water proof wood glue. I slather the glue on, and then lay the cloth across the top. Then I clamp it around the outside with about a zillion clothespins, and let it dry. The Sutton Hoo sheild was faced with leather, but I don't want to shell out that much money. I find that this makes the sheild a lot stronger. The sheild I used at Pennsic this year was made this way. It went through 1000 fights, all the battles last year, and all the battles this year. The wood (12mm poplar plywood) worked out to be stronger than the metal edging I put around the sheild, under the (at first) garden hose or (now) rawhide edging.
The second thing is to taper the crossbar. This reduces weight and makes the thing look cool. A block plane is really handy for doing this. Here's a pic
It's a little tough to see in the pic, but the crossbar gets down to about an eigth of an inch (or less) at the very edge.
The third thing is that you didn't use the stain to help emphasize the faux planks on the back. If you mask out every other "plank" with masking tape and then restain it after the first set of stain, it emphasizes the faux planking, and makes it look a lot less like plywood.
Also, you might find this really cheezy, but instead of standard washers, I hammer US 1 cent peices (pennies) until they are about the size of quarters, and drill a hole in them. Though they do contain copper and tin, it is a stretch to call them "Bronze". It does look a lot better than what I used to use.
That is a great sheild.
freiman