This is great. I actually had a similar idea, but different.
The link is here: http://www.head-fi.org/t/557103/new-power-supply-design-for-cmoy
The difference is, using Li-Ion.
I have not included the charging portion, of which is based on USB. I have already made an updated version, to what I have posted, that is for two Li-Ion, with Chargers. The preferred size of batteries I have, are the 18650 and the 14500 (AA).
There are 2 charging chips - for when using 2 Li-Ion, since I do NOT LIKE series charging, for personal reasons. It is built in "stages" (the voltage doubling) so you can either use as is, for a single Li-Ion or take one stage off for when used with 2 Li-Ion. Same design is also used for Ni-MH, just without the charging, due to that I could not get my head around NiCd / NiMH charging ;-)
Let me know if anyone is interested in the charging, part of the circuit :-)
Also Zigis, I have some very old designs I had done for the cMoy, that made it very friendly for op-amp rolling. Let me know if you are interested, schematic only. I won't mind updating the design if you are interested.
Thanks for reading guys.