Yeah that's basically what I'm doing, it's easy to add functions (and therefore ICs) when doing the component layout but the package density can trip you up, all those signals have to get out and there are so many no-go zones. Without 4 layers I wouldn't have a chance and the board would probably be twice the size. Admittedly once I decided to use one of the internal layers for signals I got lazy and stopped looking for routes on the top and bottom layers.
So far so good...
Only a few traces to go plus add the ground plane.
Rob