I like this idea enough, I wanted to pull it out into its own suggestions thread for people to discuss rather than being tucked away in the skill exp thread.
The original idea proposed was that of having potential physical ailments for older characters - but I want to take it one step further and make it something that you can take for your character.
It does tend to be generally true that one can develop more physical ailments as one ages, so I think it would make the most sense if you get, say, points you can use to "buy" these chronic conditions for your character, and you get more of those points if your character is older. Similar to the way you get more skills. So you can still play a twenty year old with, say, arthritis that acts up when it rains, or a bad knee, or some other mostly-just-annoying physical condition. But if you want to have a bad knee, and arthritis, and back pain, and gout, and an ulcer, you'd probably be looking at more like fifty plus.
(And, of course, if this gets implemented, you'd need ways to develop them through gameplay - but that seems a given.)