Congrats Mark. My recommendation would be to experiment to see what works for you. Time doesn't scale linearly with number of cubes because of reviews, but how much time that takes depends on what kind of reviews you do, and what your memo system is (how you group cubes, how many you memo before each review, etc.). Having a good system is the key, along with time management. I'm sure I saw somewhere that Maskow said the same.
So far I've just been concentrating on remembering to leave the cubes where I can find them and memoing in solve order. I tend to do one cube per room with 2 or 3 images per cube and I concentrate on the start of each image so I don't forget the whole thing. I do a no look review after each cube and then check I can remember the start of each image before I memo and solve the 3BLD cube. It works on a small number of cube but like you say I'll need a proper system for more cubes.
How come you have pieces with X,Y and Z?
By X, Y, and Z I meant any 3 stickers. Probably should have specified that
I'll be doing heaps more soon.
What's your main reason for errors? Memo, recall or execution?
I guess it has to be memo. More specifically, being able to recognize when I've memorized everything that needs to be memorized. Like just missing a flipped edge here or there.
Have you tried counting the letters in your memo? I'm not strict about doing it myself but it helps. Start with 11 for edges and and one for each cycle break and minus one for each solved piece. I get confused over flipped pieces.
