Hi,
I do think that scoring higher on verbal will improve your total score more so than scoring higher on quant. This also makes sense if you look at the statistical breakdown.. i think a 50 in Q represents a 99% score... whereas to get a 99% in V, you only need a 45 or so. So obviously lets say you get a 48 in Q.. that's like an 83% in Q... but if you get a 48 in V, that represents a 99%, so your total score will be higher. I hope that made sense.
I don't know if there's any clear way to use a total # of wrong questions to predict a score. The reason is that there are various experimental questions on the actual GMAT, so if you get those wrong it won't affect your score. Maybe someone has a better way to estimate it though.
Also check this link out, it might help you understand some more:
scoring-question-63464.html#p463526