I would likely do something similar, my only issue is that it A) Limits the amount of different images you could have, which makes any given image less unique and thus harder to remember, and B) That makes like twice as many images in your memo, which I guess is unavoidable and one of the reasons megaminx BLD is hard. Also I probably wouldn't do just A-L and A-E, since those aren't all the best letters to make words out of.
I see a lot of people talking about different methods to memorize twisted corners/edges, and I don't really get what the problem is. If my twisted corner is UBR, why don't I just memorize [UBR] [BUR]? It's executed the same way, and even if you executed twisted pieces differently, you'd obviously know it was twisted when you got there. Am I missing something in regards to why this would be difficult? Is it different for 3-style or something?
Also can someone please explain to me U2 and M2 for 5BLD cross centers? I can't quite figure out some targets, and I'm not sure which would be better (U2 or M2).