Fwiw, the AccuManager 2020 charges AAA -> D cells, plus 9V, and understands NiCad, Nimh and rechargable alkaline. It's about fifty bucks, works nicely off 12V or mains and has some very funky battery reconditioning tech: I don't know what it does, but it's taken cells I thought were dead and brought them back to full service.

I gave up on complete standardization: I figure that having a range of sizes is actually a plus, for when you come across either unfamiliar equipment which needs feeding, or can only find some sizes in the store. I have one set of everything which runs on AAA, and another set which runs on AA.