well that is an impressive project. very creative.
i didnt read much, just flipped through. are you using as5? you have a narrow delta so it should be making good contact, no problems there. u should try putting 1 or 2 large fast fans on that hc, for a test, to see if u get better temps. you might be feeling effects of lower airflow accross the heat exchange. if u get better temps with fast fans, then u know nothing is wrong. warm temps arent a big deal imo, its working good.
just some thoughts