To be honest, the only two aspects of my outdoor activities that now translate into needs are my fly tying and knives, the tying because I will always tie, even when I can no longer get to the river, which I pray is a long time from now and custom knives because you can't have too many good knives.
The other stuff, I am looking at downsizing a bit, haven't told my boys yet as they would raid my stuff LOL

To the OP: as mentioned, decide upon species, water type and fly gear then start looking into effective flies. Its an addiction like no other....well maybe women and good Scotch.