The voltage divider on the output is not a good idea. It raises the output impedance and causes a lot of quiescient current draw. Surely there are 3V regulators out there that can handle 12V in, but if you can't find one for some reason you can use a adjustable regulator. That seems to be...
Hi, Bob. I see you're in Worcester, but I otherwise can't tell who you are. You make it sound like we've met before. Care to elaborate on who you really are?
Normally when stepping down so much (1/4 of the input voltage in this case), you'd use a buck converter for efficiency. However, since your load only draws 7.7 mA, the dissipation in a simple linear regulator is only 70 mW. Even something as small as a SOT23 package can handle that without...