Just a note, but you're using awfully small hexes and large points there. The two plots approach each other asymptotically, especially if you switch to a monochromatic colormap like some here have argued for.
Histograms tend to work best when the data is well understood, while scatterplots are better for samples from an unknown distribution (incl. lattices, multimodals or even double exponentials).
Try also small samples. When the piecewise uniform prior (on both the data and the intensity) is approximately accurate, histograms are far better, as they guide the eye away from nonexistent patterns. But the bandwidth needs to be judiciously set, and often the data transformed.
I have 20-70 data points per hex, at least in the high density regions. While I could have used bigger hexes, I think the difference between a hexbin and a scatterplot is well illustrated.
Histograms tend to work best when the data is well understood, while scatterplots are better for samples from an unknown distribution (incl. lattices, multimodals or even double exponentials).
Try also small samples. When the piecewise uniform prior (on both the data and the intensity) is approximately accurate, histograms are far better, as they guide the eye away from nonexistent patterns. But the bandwidth needs to be judiciously set, and often the data transformed.
Clustering is hard to automate.