I created a green isometric cube pattern using the pattern maker tool in Illustrator CC. I loved how easy it was.
Then I thought I'd try something a little different, and after a bit of fiddling around I added a seamless hedge texture to the top side of the cube, and adjusted the other colours to match.
I also had a go at creating the pattern using the technique you described for Illustrator CS5 and earlier, and it worked a treat too. It's good to know some of the different ways to do things in the program.