CPU Fan
You could save some here depending on how far you intend to OC. If you don't plan on going past 4.3-4.4GHz then you should be ok with the Coolermaster Hyper 212 Evo at only £25.
RAM
Anything over 8GB gives very little benefit when gaming. If this machine is purely for gaming, save some money here.
GPU (maybe...not so sure on this)
Depending on your monitor resolution you could save nearly £60 by getting the 2GB version instead of 4GB. The performance increase is supposed to be negligible on anything 1080p or less.
Thats about it really. Anything else you begin to sacrifice performance/features for the savings.
Nice build btw