It depends on your rig.. In most cases (considering a general gaming build nowadays) a single front intake fan along with a single back exhaust fan works well.. Coming to your query, there are few structural errors (IMO) with all of your proposed setups.. All the diagrams show a back exhaust fan which is good.. However, having the front intake fans at towards the top is not understandable.. Also, in diagrams 1 and 3, you've mentioned the top fans to be intake which is unnecessary.. They need to be exhaust fans.. Diagram 3 shows a bottom exhaust fan which is unnecessary.. Diagram 2 seems the most practical except that the front intake fan should feature towards the middle or bottom portion of the front of the case..