Be prepared to do a good bit of hand rework in node mode. If its a so-so quality image you arent getting anything worth the effort. Hand tracing isnt that hard once you get the hang and a pair of good reading glasses.
I think hand tracing is the route for you.
X3 and X4 users could put the image into Powertrace, merge some of the colours and slide the detail control to the left to get a useable outline at least node editing would be reduced.