Using duckduckgo.com - which doesn't track users so should give the same results for everybody - I searched on
air fare discounts for seniors.
Within the first page I found lots of sensible results the most interesting IMO being
Exactly how useful that is may depend on what you have in mind. Is this to go from A-B or the bucket-list trip you were talking about going from A-W with all points in between?
Thoughts. I'm a senior but by your admission I'm a lot younger than you and already I'm becoming averse to 48hr journey times with three transit points or a twenty-three-and-a-half hour layover at KBP [1] just to save a little money. I now have to look after my health as well as my wallet.
Don't forget that BAExpat
@ben is a travel agent and a very good one. Tell him what you want and, senior discount or not, he'll get you the best and/or cheapest and/or least exhausting flights available using trade resources that amateurs like you and I would be unable to access.
[1]Yes, I know it's closed for the time being