I've only played the base game, but I want to pick up the GOTY edition. Has all the outfits and Challenge Map DLC, so there's that.
As far as HQR goes, from what I've seen of it online (playthroughs), as a standalone DLC, it isn't worth it. As part of the package, it's acceptable. I wouldn't pay $10 for barely 2 hours of new content, especially when half of it seems to be rejiggered maps and setpieces from the regular game. They even took the HQR end credit music from the "mourn your parents" scene in Crime Alley.