Ten years in any one position or ten years total in any elected position?
Career politicians have their downsides but for stability you do want a portion of experienced people. Governments comprised entirely of ‘fresh blood’ tend to be a steaming pile of garbage because no-one knows what they’re doing.
Age quotas could be a reasonable solution, if you had an MMP or other proportional system involving members elected at large rather than every election being a direct election.
Definitely; look at the railings in the stairs at the far left.