wondering if the ctr on an ad in adcenter would maek the clicks cheaper, or is it totally based on QS?
It's based on the quality score, but if your ad's CTR is high enough it will improve your quality score too as now the system algorithm can tell your ad is relevant to the keywords you're bidding on. CTR is always an important component to determine your CPC in lots of major networks, whereas high CTR doesn't always mean to be a profitable ad on your end. It really depends on what your approach is.
Hope it helps a little.