"We experimented with a numerical scoring model some years back -- it just didn't work. Brought in all the senior people, sales managers, product managers, you name it. We selected several dimensions of technical and commercial viability, not too different from the scoring model you presented. Rated everything on scales of 1 to 5. Guess what? All the projects that were the "pet projects" of senior management came out as 5's. The ones they all could care less about came out as 1's. And all the ones we really lacked good information on came out as 3's. A lot of help that was!"