Need help with outer case fan

Hi, so in 2014 I bought my PC Online. My case is a Sharkoon Bulldozer and has come with two fans already mounted one at the front on the bottom, and one at the top on the back panel. I recently upgraded my GPU and PSU, and I am worried about cooling issues. If anyone can suggest a good fan for the mounts at the top of the case it would be greatly appreciated. Also what is a good fan for cooling the CPU? My current i5-4690k @3.5Ghz has the stock cooler and I'm told to upgrade the fan, but not sure to what. Thanks for reading

That case doesn't look that bad for air flow . Do you plan on overclocking? If not you will be fine with the stock cooling.
If you are looks like you can fit a 2x120mm rad so a Aio system might be a good option.