For a case the size of the 200r,just 2 fans is normally sufficient, 1x low intake and 1x top rear exhaust. With 4x fans, use 2x intakes and top rear-rear exhaust. You really don't want to use the side mounts as intakes, they just create too much turbulence and heat is blown around in the case. If any usage of the sides, it should always be exhaust. Several reasons for this, including, there's no dust cover on the sides, gpu exhaust heat is drawn out of the case before circulation, makes for a cooler cpu.
Unless you're using a very hot running gpu, normally sides are not used at all, optimum airflow is reached with 2x in low front, 2x out high rear.