Yes, the 10 episode format is one of the main reasons why I stick with J-dorama. It's more straight forward, no circling around the plot (which often end up being ridiculous), and short. I find US drama format is ridiculous, lots of the drama that I find interesting is only interesting for 1st season, and after that all go down the hill as the writers run out of ideas. The only US drama that I'll watch is CSI (not Miami and definitely not NY), I even stopped watching Bones LOL.
I have to add one thing on the villain part for the fun of it, they seem to live in the drama just to screw over our hero/heroine, the amount of hatred and obsession that they have invested is telling us that they're too free. At least the villains in J-drama do something else and while at it screw over our hero LOL.