Nice writeup of your installation, thanks.
It took me rather longer than 10mins to install but I was rather nervous and triple-checking everything
I actually got a bit annoyed with the adhesive backplate as I had to remove it when it turned out to be machined wrong and I was a bit uncomfortable with how it pulled on the motherboard when I was pulling it off but I don't think it's done any harm. Even if it had been machined properly, I may have stuck it on wonky or I may want to change the cooler one day so I think it would be better without the adhesive. Obviously that would make it a bit harder to fit as you need to hold it in place whilst putting a couple of the screws through on the other side but I managed that (when I was testing by putting it upside down, so the adhesive was away from the board) so it's not impossible (or if you have someone else who can hold it in place for you, even better).
I was a bit worried that the heatsink didn't seem to be sitting flat when I started fitting it but I think once I'd fully tightened it up, it was OK (temperatures look great anyway!) I was mounting on AMD, so it might be different for you but your tip about only fitting one spring at a time sounds useful.