I've been thinking about trying to formulate a lith developer also. My favorite is Rollei/Maco/Labor Partner with Moersch coming in a close second. They are both expensive (Moersch) and/or supply is spotty (R/M/LP). I'm nearly positive that the Moersch is formaldehyde-free so it is possible to formulate a good, stable non-formaldehyde developer. I'm using Arista and some Nacco I have around for now.

Also, I tried the acetone route and it is definitely not a 1:1 replacement. It didn't work all that well.