OK, first thanks everyone for all your input. Here's what I think I am going to do.
As I have all my images currently organized by year, I think I am going to keep that strategy as a catalog. My file names are off the order YYYY MM DD Place-name (or subject) Camera. So a file from today's shoot in the backyard would look like 2015 05 29 Backyard D4s. From there, I am thinking that collections or smart collections would be the next step, and I think there could be a great number of these. I'd start with the place name or subject as the collection title, and possibly/probably add additional key words further refine or drill down. This could be as generic as something like Bird or Mammal, but be in subcategories under those (assuming a subcategory is possible in collections), something of the nature of Raptor or Bighorn. I need to learn more about collections and how they behave.
My added meta data will be pretty simple. Just stuff like copy right, etc..
Right now, I am doing almost all of my photography on my laptop, as the OS on my iMac is too old to handle the version of ACR that I need for my D4s, so I am going to have to think through how I handle that. Most of my files are on external drives, and I think I am going to make that more or less the rule, that all files are on external drives. So, importing from camera or CF will be to an external drive, possibly to a second drive at the same time. I will certainly back up to a second drive.
I am going to make an appointment at the Apple Store to find out about upgrading my iMac. I really don't want to buy a new one, but a bit more memory and a current OS would be nice. That presents the challenge of getting the two machines in sync, but I suspect that it can be done.
If anyone wants to comment/poke holes in my strategy, feel free.