I have used the 200r in a couple of builds some time ago, I didn't need to add any fans - the 2 fans that come with the case are pretty good and can handle most non-oc cpu / gpu without any problems, with the usual front intake (helps to cool HDD) and a rear exhaust (helps keep the motherboard VRM temps low). That being said, if you are going to OC then it may be a good idea to add a top exhaust just above the CPU, and maybe a side intake in the lowest fan mount (if you get the version with the 2x120mm side mounts, which is going to be best for OC cooling).
Most cases use low front intake and a high rear exhaust to keep air flowing which works with the natural convection of heat rising.
Good read here:
How to Manage Your PC’s...