I love the Z but personally I wouldn't make the trade yet. You've had a few problems with the Hyundai but you're still covered by a warranty. I know it can be a pain but those aren't exactly huge issues you listed.
Keep the car for at least another year, save your money and then decide what you want to do. IMO, throwing away your money over a few minor issues is something you're likely to regret later. That's money you could be spending on mods!
