It’s really not a question of what you can do with the skills you have because those skills will transfer to just about any field well enough to get you a start. You need to pick something out that would meet your needs (happiness, stimulation, money, whatever) and make that a target. Then build your skills to match, just like you did for your Sysadmin gig.
Customer Service, technical know-how, and analytic skills are basics that will serve you well anywhere, and every business has an IT component at this point. Build a bridge from here to there.
If you’re looking for a place to start, there’s something you enjoyed about systems administration that drew you to it in the first place. There’s probably some portion of your job that you enjoy now as well. Try to expand on that.
If you occasionally write scripts and enjoy that, you can follow that a long way with programming.
If you enjoy setting up networking architecture, that’s a huge field and very much in demand. There is so much training out there you could never learn it all. Get some.
If you like the web, there’s a million directions to go there and you can see the best in the world and exactly how they made their magic. Try something out.
If you find you really enjoyed learning new things and just miss that where you are now, maybe it’s time to go deeper with what you have. Attend a conference, get a certification, start a side project, join a trade group.
I don’t think anyone can tell you what will make you happy, find something that feels good and follow it.