There's about 7c difference between Spire and Stealth. Either is adequate for it's corresponding processor.
AMD upped the game with the stock CPU coolers it bundled with Ryzen processors and they kicked it up another notch with 2nd-gen Ryzen which come with...
www.techspot.com
Temps will vary depending on case cooling and climate as well so hopefully you have some intake & exhaust fans and reasonably cool room to help.
If want to overclock, consider an aftermarket cooler like the Noctua D15 or Dark Rock Pro 4 if your case can accommodate.
You'll enjoy the 3600 or 3600x more than the 9600K, that's for sure. 6 core cpus just aren't cutting it anymore really.
I recommend fitting your rig with ram in dual channel between 3200~3600MHz for best performance. 2x 16GB would be ideal, setting you up now and into the future.