I've used WinDirStat before, and liked it. It was almost like treasure hunting.
Ding ding ding!
WinDirStat is the best thing since sliced bread IMHO. Extremely useful for small SSD maintenance and care.
I'm assuming that you haven't configured Windows to truly operate at SSD level... see here. The pagefile and hibersys files being gone should free up about ~20-30GB.
Follow the other steps listed above w/CCleaner and removing temp files... Windows sucks at doing that and should have it's own special on "Extreme Hoarders."
Just the two above should get you back in business. Let us know