i did see the fan percentages under the 1 fan speed showing. I wonder if HWINFO would show all fans. I know it can't see my AIO ones as they controlled by Corsair but it should see more than just 1 speed. Especially as you using 7 headers.
You don't have to do this, it might just show more fan speeds -
Download HWINFO - https://www.hwinfo.com/download/
when you open the app, click the tick box next to show sensors only, and click run
in the next window, click on the gear icon in bottom right, this opens settings.
On General tab, under polling period, set it to 500
and click the set button next to it, and click OK. this reduces the amount of time between sensors updating so its more accurate and you can watch CPU fall and rise all day.
I used tips from this video to set up icons in toolbar to track two temps but not the ones he chooses, I went with Core Temperatures
instead of the package temp
Core Temperatures is average temp of all cores and ignores the constant spike of a core being woken up every second or so.
If you want to know actual speed of CPU at any one time, the best to watch is Core Effective Clock
Another thing you can do it set it up so it shows graphs of scores you are interested in and can watch onscreen. you can do this via right clicking a sensor value in main menu
and they show like below:
There are OSD controls as well but I don't use those so I am sure there are guides on internet for those now
There are downsides to having AIO as exhaust. It really depends on the GPU though. I doubt a 4070 is as hot as say a 4090 would be. Using AIO as exhaust above a 4090 is a great way to cook your CPU as you have to remember the AIO is there to cool CPU, if its taking hot air from GPU into radiator, its source of any air is the case. I have mine as intake on front of case, its source of air is outside case
it can make a difference
Your case can probably cope with it where it is though. 6 intake means not a lot of anything stays inside case for long. Though if I had that case I would mount the 360mm AIO on the side panel as an intake, as the heat from CPU isn't that huge compared to GPU.