Age is not an issue-greed is-at any age. I like term limits-say no more than 8 years in senate or house, then back to your old job as a business owner, dentist, lawyer, whatever, but with some resume enhancers-pres only gets 8 years, so that seems fair. With only 8 years to hold the job, the grifters won’t have time to make a legal killing financially, so they might not find the job so attractive...
The brilliance of the founders came up short in the one important area of term limits.