About your 2nd image
jaydee116 when I was playing around with my clover block in its experimental stages, I had wanted to do a single inlet and single outlet. But whilst doing some CFD analysis on the flow, I kept on noticing one small problem with it, this;
Fairly large recirculation zones in the areas furthest from the outlet.
Adding another outlet solved the issue quite nicely. But that was specific to my design at that time.
Basically, with your second pic, I feel that the cooling efficiency of the outer pins furthest from the outlet wouldnt be up there, they'd more than likely have fairly stagnent water flowing around them.
The Cascade got away with the single vs. dual outlet issue to my knowledge because of the jets. Each jet forcibly evicted the water already residing in the cups and since that was where all the cooling effectiveness of the block was, it wouldnt have impacted too greatly if part of the block exhibited stagnent water flow.
Hope that helps a little.