It's a small improvement in a lot of metrics but it's only a 1-generation increase. IPC, clockspeed, overclocking ability are up, power consumption is down, and it has a few more instructions. However, be aware that it still doesn't meet the minimum requirements for some games.
I would not spend more on a cooler. Newer Intel CPUs draw far less power, and a Hyper212 is plenty even for something like an i7 6700K, which is something like 3-5x faster.