These are my idle temps on water with two 420mm radiators. I feel they are a little on the high side but my ambient room temp is 24c.
Which temp specifically should I be watching just to keep an eye on my CPU temp?
your lowest power draw is 59W... you should first look at reducing the load of background tasks probably, since your CPU seem to rarely idle at all. CPU usage minimum is 4.3% which is quite a lot for a 32 threads CPU.
Otherwise, just look at the temp you have highlighted in green + the two CCD temps
As I know, the most important temperature to monitor is the CPU Core Temperature. It should be between 30-50°C (86-122°F) at idle and 60-80°C (140-176°F) under load. If it exceeds 90°C (194°F) under load, I recommend cooling down your CPU.