The first things I would do is convenience items. Mirror movers would top the list, so you could safely take the doors off and drive around town. The best thing about a 4-door Jeep... is two more doors to take off! If there's a garage, you could pick up holders for the doors when they aren't on.
If you plan on wheelin' it, you can do your first couple runs stock, so I'd be thinking about a Hi-lift jack for ease if something goes wrong and/or a winch. Definately a tow or snatch strap. Lots of info on here about those.
On your list, a snorkel would be cool. I was surprised how much a K&N drop-in did for throttle response on my first TJ, so that'd be good, too. Check out any "free" upgrades like removing restrictions in the airway. Again, not sure how that relates to the JK.
I echo that it all depends what you want. Personally, I'd wait until the stock tires begin to go before thinking lift and tires. You paid quite a bit for them already. Whatever you do, enjoy the thing. I love the Unlimited, but my pockets don't allow for it.
-X