Make the verbal better.
can you be more specific. what needs to be improved?
Put up some medium level/tough SC problems, and some good Critical Reasoning questions that use the same kind of logic as those used on the test. On CR, a common thing I see for tough problems on OG are passages that include on unnecessary word to throw off the test-taker. For example, the passage would talk about "population growth" but will have answers that deal only with "population" (not population GROWTH) to throw off the test-taker. For RC, I would suggest putting in A LOT of tough science passages, considering the fact that these give the test taker the most headaches.
I know it sounds kind of hard to do, but Im sure you guys could do it.