70 ad groups is to much to test to get any knowledge.
test 1 ad vs 1 ad. find the winner, and put it against another ad.
once you make some good improvements, test one LP vs another LP.
when you get a decent LP, test headlines.
Now, go back thru your ads to better fit the LP
then test adcenter response vs adwords.
test search vs content.
test LP colors
test Long tail vs short tail.
test long copy vs short copy
test highlighted text vs non.
test monday vs tuesday
test weekdays vs weekends
test work hours vs beer hours
test east coast vs west coast.
1 vs 1 to get a good idea. to gain experience. You need a good amount of response to test anything. 10 clicks won't do it $100 a test seems to be a good guideline around here. and TRACK YOUR TESTING