Coincidentally, I had already dug up another post somewhere that demonstrates that particular plugboard and I'm currently using it. It's pretty great
I'm currently trying out a new organizational scheme that involves the plugboard linked above as well as a custom "Genre" field, which is the only thing I create Collections from on my device. I use the "Tags" column only to group together related books that aren't part of a numbered series, like "Star Wars," "Warhammer," "Dragonlance," etc. When I send books to the device, I have Calibre put the series, series index, and tag at the beginning of the file name, so if I sort a Collection by file name, books grouped by series and/or tag end up clustered with each other and easily located. I also use genre names like "Science Fiction.Space Opera" to break up what used to be large genre collections.
So far it seems to work okay for me, although I haven't had a chance to fully test everything out yet. But so far it's better than what I had before, which was causing me to exceed the maximum number of Collections allowed on the T1.