Need suggestions: Beginning anew going forward, go back later

I'm so glad that I found this forum. I've yet to even scratch the surface of this valuable resource. I asked a GPS question here recently & gave as a reason the possibity of using place names in my file names. Several posters offered advice against doing that. I "defended myself" in a couple of follow-up posts, but that got me to thinking . . . I really DO need to "clean up my act". Thanks, again, to those who "challenged" me. I'd appreciate any/all suggestions for direction.

First off, I am not a professional, but I love photography & I have many thousands of slides & digital images in my archives. Originally, with my slides, I had a workable (for me), but far from perfect cataloging system. I could locate slides by multiple categories w/o great difficulty. However, I was overwhelmed by the administrative side & after a few short years fell behind, never to catch up again. A major problem is that most of my images were/are from photo safaris. Before I was done with processing one trip, it was time to leave on the next.

Digital just multiplied & complicated things. Basically, I culled the rejects & renumbered (adding very brief descriptions that I sometimes searched on). For retrievals, I mostly relied on my memory & reviewed thumbnails. My biggest problem was that I was overwhelmed, because "I'll never be able to properly catalog all archives". It's simply too big a job. I want to change my thinking to "one step at a time", starting now to manage my future images & working back thru my archives, as I can, selecting the most important groups 1st.

I studied some of the presentations at dpBestflow.org & now have some wheels turning in my head. I don't want to wait until I have the "perfect system" designed before I start. I want to start while I'm "excited" about the project (& the prospects for improvement), but I also want to make sure I'm headed in the right direction. The thoughts below are, more or less, as they popped into my head; definitely not ranked by importance. They're not all inclusive. There'll definitely be more.
•   I suppose, I might have a few unique key-words, but surely somewhere there's a good "master" list, hopefully, with synonyms. I'm sure I won't purchase the most high-end software, so I might have to do some kind of look-up before actually entering the key-words. I'm thinking of using Bridge now; maybe something else later, if needed.
•   I always shoot with multiple cameras, with carefully synced clocks. I have renaming software for prefixing date/time for merging images into sequence. Then I assign MY numbering system. I'm pretty pleased with the numbering portion of my present system. It may be the most salvageable part of my existing method (or lack thereof).
o   YYYY
o   99999 (within year)
o   XX - code for Country/State/etc
o   0 - original (1,2,3... for other versions)
o   1,2,3... if other version is further modified
o   descriptive
•   Way back with slides, consecutive numbers ("99999" above) seemed important to me as a way of accounting for all images, so I would go thru the culling process before assigning my final number (that always seemed out of sequence in my workflow). Now consecutive numbers seem less important (for whatever new system develops).
•   I used to keep panorama "parts" even after merging. Now I just keep the stitched image. There's still the possibility that part of a pano might stand-alone as an acceptable image, but those could be kept (not deleted) during the culling process. I used to name (#) panos YYYY-12345-12350-NY-0 (for instance, when I was keeping all the parts). Now I just assign a single number, but add a suffix pano(6) to the descriptive part of the name. Knowing "how many" just seems "nice to know".
•   HDRs presented a problem when keeping consecutive numbers, because I'd have to process my HDRs before final numbering . . . again, disrupting/slowing/confusing the workflow. Sometimes the "even" exposure is my keeper & the brackets are deleted.
•   Most of my archives are on 1 of my 3 external hard drives, which are usually off-line. Only relatively recent (& other selected) images are on my main HD. I'm thinking that (after fully implementing my new system) I could make small jpgs & store them on my main HD w/o using much space. They would contain all the metadata & could be search very quickly. Of course, I'd then have to access the externals to get the actual images. That's less than optimal, but workable. As is, once images are moved to externals, the odds of their being retrieved again drops drastically, simply because it's inconvenient. I don't have clients asking for specific retreivals.

Thanks in advance for any pointers.

Jim