great question OP, I too seek a registrar that is king of kings in all ways.
Originally I had great results with enom as a 6.95 reseller. Then when I needed support it was not existent. Franky Chung is supposedly my reseller to turn to for all questions and he has not once returned an email or phone call (12 years of this) Their general support sucks and knowingly deceives.
I once backordered a domain name I let expire and won it, yet they still kept it - does it get any shadier? On the phone they continued to direct me to my parent reseller who may not even be a real human.
Like Jack I setup some reseller and retail accounts a long time ago and have been their customer support. (some accounts still are able to renew at 8.14 (old minimum retail despite the 6.95 base going up)
Godaddy with reseller club isn't a shabby choice. 24 hour support, auction perks...