I think this is brilliant. I would go with health in the postcards, over medicine. And I agree with @livinguktaiwan--moving it to 55 might be a good idea. When I took a writing workshop for 'seniors' the cutoff was 55, and we did get people in the 55-60 age group. Also, a lot of people (in the U.S. anyway), are eligible for retirement at 55.

This is so well structured.

I'll be a cheerleader and supporter in any way I can.