Came across this little gem, Imagine. This seems to be the closest to my needs so far, I think. Keyboard shortcuts during fullscreen are different / not customizeable (Acdsee 3.x can't either) is the only slight complaint I have so far.
Although it hasn't had much development lately, you can also give Imagine a try, it's free.
Get the Unicode version and don't forget to grab the plugins:
http://www.nyam.pe.kr/dev/imagine/