Heres my take on what you could do. I will start with the bad news first so we have a happy ending lol.
For under 2000 credits you will not get the clubs that will help you long term. You are growing in levels very quickly at your stage and as pointed out, the higher levels bring better clubs. Yes you can spend the credits now and you will see an improvement in your game, but you would quickly outgrow these clubs.
You could get a set of Lvl 32 R11's irons (1995cr), great clubs but do have a faster meter speed than your existing clubs but will last you a long time But thats no upgrade in driver or wedges.
Now the good news, you are scoring well with your existing clubs, so take your time to learn the game more. At TP distance is not such an issue from the tee (excepting a few holes) and for a minimal amount you coulld get a couple of the Ping Tour Wedges (lvl 18) at 110cr each. This will help your short game a lot. Basically the starters wedges are the worst clubs in your bag. There are better wedges available later but for the cost vs improvement in your short game, these wedges are worth it
When you do upgrade, I think it is worth getting a set that will carry you through to Masters/TM. In the meantime just enjoy the game and work on your short game.
And for Lonnie - no I am not a sales rep lol!.