It sounds like you're doing the right thing. Just remember, the need for pilots is shrinking. That may be the only reason why having a large network of friends hasn't gotten you your dream job.
I've always been praised for my ability to network in this industry, and I've created several jobs for myself because of it. Those are the only things I've got going, and they aren't that fancy. I can't get a part 121 or 135 job, even with an ATP. That's just how it is. I have great friends in great places in this industry that pull for me, but if I wasn't passionate about aviation, college and flight training would've been a complete waste of time and money.
Like you, whenever I'm at an FBO waiting, I try to strike up friendly conversation with anyone when the situation is appropriate. You never know who you'll meet.
Sometimes the area has a great effect, too. Ventura County has more Gulfstream aircraft based there than there are from San Fran all the way to Alaska. I don't know where you live, but if you want to really jumpstart corporate, hanging out at Teterboro or Van Nuys can't hurt. You can network all you want in Nebraska but you're less likely to land a job flying a Citation there, perhaps.
I wish you the best of luck. You sound pretty well set up already. be thankful you have the experience you do!