Hi Rob - you are doing quite well with the equipment that your profile shows!
As you "upgrade", keep in mind that matching the meter speed of all of your clubs will help a lot.
I am listing the "upgrade clubs" in the recommended order of purchase. If budget is not a factor, have at it, but the clubs that will do the most for your game begin with the wedges.
1.) In order to improve your "short game", you will need a set of Wedges. Better players on the site recommend Cleveland 588 wedges and carry/play 3 of them (64, 60, and 56). Read what others have said about them and (more important) tips for using them. They are very, very accurate inside of 100 yards but you have to learn how to control the backspin. The meter speed of these wedges is 3.5.
2.) If you can, I recommend that you wait for 1 more level (85) and buy the Nike Vr Forged Irons - they are superior to just about everything else that will be available to you until level 90. Their meter speed is 3.5.
3). Driver: I used the TaylorMade Sldr (L79) and it was pretty darned good. The Callaway Big Bertha Alpha 815 (L83) has about the same stats but sends the ball out at 9.5 degrees instead of the SLDR's 9.0. The 9.5 club will lift your ball higher and be more adversely affected by wind. Both clubs advertise a meter speed of 3.5.
4). Fairway wood: The TaylorMade R15 (L 84), with a meter speed of 3.0 will serve you well for quite a while.
5). Putter - please see the putter precision test thread to choose. (http://www.wgt.com/forums/t/195080.aspx?PageIndex=1). I prefer the Nike Method Putter.
6). NOTE: When you buy your new clubs, you will want to "index" them to learn how they perform. (read about "indexing or dialing in" in the Search box to the right of your screen). In order for the "indexing" to be meaningful, you will have to use the same ball for the test as you intend to use for every day play.
7). Ball: The Callaway L33 Soft Hex Chrome is a consistent performer (i.e. doesn't do weird stuff randomly) and only costs 250 credits. Many really good players use these until they need the "super dooper high dollar" Nikes for specific performance improvements. Unless you have stock in WGT or really need to slow down the meter, those Max balls are WAY too expensive for everyday play.
Good Luck!