You could relax and enjoy your system cause it is working fine as it should.
Or you can find yourself without the best system possible, and spend money to improve it.
Note that not all games will be as intensive on processor as others. Most aren't, so you're fine in most cases. On extreme cases there is always an upgrade that will help you, or help anyone, but there will ALLWAYS be something for you to spend more money, the decision to bother or not is yours.
Rest assured (by your 3Dmark11 scores) that your system IS working fine. A stronger processor will improve your scores, as well as a new video card, or SSDs, more and faster RAM, etc., etc., etc....
I would say, if the specific games you want to play isn't at ENJOYABLE fps, think of spending more money.
Though you are running Metro last Light with SSAA on at 52 fps. That will run every other game at 50+ fps so everything woill be great for you!
In your place I would relax and choose some new games to play.
(and also read a lot and learn to overclock the 2500k to 4.5Ghz in a stable way, overclocking CPUs is a lot more detailed and difficult, and also requires a lot more patience than overclocking GPUs)
Ps.: I had a 2500k just before the 3930k. To run stable on 4.5Ghz mine took almost 1.4V, and on air that required a pretty decent air cooler.