Should i upgrade from an i5 4460 to an i7 4790/K

Hi Community

I am still undecided on if I should get an i7 4790 to replace my current i5 4460 as I'm seeing very high cpu usage in games with the i5 on the Witcher 3, Fallout 4 (works a lot better than it did 2 months ago as back then my cpu would be maxed usage now it goes 60-80%) and Killing Floor 2.

Would it be worth the price? As its like £230, would I have a big boost in performance or am I only really just getting 8 threads compared to my i5's 4..

Also my temps are 30-60 celsuis with stock cooler.