John,
Like you, I buy only premium fuel which is as you state, somewhere in the 92/93 octane range. I don't add any "lead", I don't use racing fuel, or avgas, or any other non-standard fuel. I do add, a couple of times a year, Techron fuel injection cleaner. I usually add on container of that per tank before a long trip--so it does its thing and doesn't remain in one of those tanks of fuel I don't use all that often.
Like many in the northern climates I store the car in winter, with a full tank of premium and the requisite amount of Sta-Bil fuel stabilizer in it. That full tank will get completely consumed on the spring trip home around mid-April.