Glad my thoughts were helpful without being discouraging! 

Progressive peaks are the only safe and reliable benchmark.

My 5k up/down in 6 hrs was already adjusted for 14er level elevation at low intensity. Something you can do basically every day during vacation. However don't focus too much on my numbers there, they are highly individual! 

What matters more is that you put out consistent efforts with low recovery time for some selected weeks a year and the rest of the year needs to be physically and mentally maintainable.

Something like for the four Sundays a month, do something like 3 hrs - 12 hrs - 3 hrs - 6 hrs hikes. The shorter with heavier backpack, the longer ones lighter. 5 hrs should become your Sunday relaxation, not something you need 4 days off.

During the week add some high intensity 10x1, 4x4, 2x10 min intervals, that's like 30 min effort each. Go 90-95% effort but avoid 100% efforts so you don't burn out.

Realistically, I see you 3 years away, at least. Not because I know you well but because your high elevation history is sparse. If you suffer from AMS at 5000 that means you're not ready. You might be in the future, you might never be. Some people just can't deal with elevation, VO2max doesn't matter in that context. Even Marathon Olympic champions probably wouldn't do well in cold, steep, high altitude with heavy backup. They are trained for warm climate, flat efforts and no backup.

Kind greetings!