Hmm.. I re-read this thread three time to try to determine what I'm missing. Your GPU temps and utilization are good. You CPU temps are good, although I'm somewhat surprised that your CPU utilization is above 90%. I honestly would have guess that it would be lower.
Question: When the CPU usage is above 90% what are the precise CPU core temps at that time? I just want to be absolutely sure that it isn't throttling, causing a degrade in your gaming performance. Sorry to ask you a question that sounds redundant.
* Two things occurred to me, as I have hands-on experience with the 970 and not the 760 SC: (1) Either that going from a 760 SC to a 970 is a lateral upgrade. I wouldn't think that this is the case because the 970 is listed three tiers higher on the Tom's Hardware graphics card hierarchy list. Or (2) the 760 SC either came with an incredible overclock, or you personally overclocked it further in the past, close the performance gap between the two cards. Can you increase the core and memory overclock on the 970 and see if that helps? I would leave the voltage alone.