Thanks, John and Steve! Kirk, I might need to take a break from finishing lists for a month, but look for me again in July.
Summit County's Gore 12ers and 13ers definitely include some worthy peaks. And I enjoyed the peaks < 12K here this past winter and spring. The views of the Gores across the Hwy 9 valley from the peaks to the east are pretty cool.
Lake was an obvious place to start looking at counties, since everything is over 10K, but I did do a 9er to finish Summit! Maybe there's hope for me after all.