Wow, you really have that 'digging under' question licked I'd say, and it does look really secure. I have to say that I'm a country girl (old though so not such a girl!) who has a very tight coop, but beyond that I'm philosophical about losses. Not everyone understands that attitude, but when you grow up with farm animals (cows (dairy and beef), goats, pigs, chickens and horses and ponies too) beyond doing the best you can at any given time, and balancing the risks, you then accept what comes. ...though back in the day we didn't have neighbors so close so shooting varmints is more difficult now!
A lot of people find that harsh, but it is what it is. You have obviously done a great job and are going to do even more with the electric.
One problem I see with a 48 inch tall woven electric netting is that it will do a super job of keeping out any climbing varmints and possibly bears, it will probably discourage pigs because they'll nudge it with their noses first and that's pretty sensitive... but a bobcat will simply jump over it. Plus it's more expensive to buy and operate.
With your setup, (which is beautiful BTW) I still say 2 strands, right on what you have there, 3 if you really feel strongly about it, would be more practical if your biggest worry is indeed bobs. Either way, keep us posted because you have put so much thought into it all.
Oh yeah, chickens ARE easy to keep, and fun too as I guess you know. And educational too! Where else would you get so much practice building Fort Knox style enclosures and using every bit of ingenuity you can manage to figure out how to keep them alive?