Thank you for these tips. I've followed them and received pretty much the same figures as you. Saved me a lot of time and hassle. I could make it up to 21, but not much further for it to be stable, too hot or too noicy. Now I am mining at around 19-20 stable. I have global work set to 4096.
One little tip back is to add "exit" on a new row last in the bat-file that starts the miner (in your case start_nanopool.bat). That way you don't need to manually close all DOS-prompt windows which are generated by the scheduler bat-file (which was an awesome idea btw!).
Also, I've noticed that setting a timer for 3600ms gives me less pool offline notifications via email on miner going offline.
(Miner just sometimes stops mining but without crashing the rig, so reducing the restart timer helped with that).
Cheers!
RE: ASUS GTX 970 STRIX - Mining Ethereum with 22MH/s?