nah I'd say 65 is sufficient. Usually you don't start leading an entire entity until your 50s (your 40s tend to be you as a lead of a division but not the whole show).I agree and id say like 55. They need to be able to live through their political consequences with a clear mind before that senility sets in.
And make this every office because the local city council here in charlotte is fukkin up big time. Just because they are local doesn't mean your 2 min allocation at a once a month public meeting means anything to them.