The only other objective difference between the two, is Infocus seems to push/bias green toward yellow a bit (undersaturate it) while the W5000 (and presumably W20000) actually have primaries that are closer to correct (though a tad oversaturated).
Going from my IN76 to my W5000, one of the biggest differences was in the "improved" color, they seem much more vivid on the W5000. Note that that's comparing a 720p to a 1080p, though I think they're both DC2 machines.
The only other comment I have is my IN76 was rock solid, while the W5000 seems less so, however I think I had a "late" revision firmware on the IN76 and the launch firmware on the W5000, so I'd be willing to accept that I just got the IN76 at a more mature point in it's life cycle.
If I could have dealt with the offset, I probably would have got the IN83 when I was purchasing, and if f300v10's info is right (I haven't followed that closely) I'd probably lean toward the 4000:1 native contrast of the IN82 vs the ~4000:1 dynamic contrast of the W5000, but I'm not sure how I'd weigh that against the better colors. FWIW, I didn't feel I was missing anything with the IN76's colors, it's just that the W5000's better colors were a nice surprise.
Hopefully that's not more confusing than helpful