Recommendations for low-poly rigs

I’m wondering if anybody has a good reference .blend for a good humanoid rig complete with weight painting and such. I asked one of my friends about the best ways to do things, and haven’t really gotten any concrete advice. I also realized that they only do super low-poly (like…N64 polycounts) and super high poly (film) characters, so I guess I’m looking for a bit of a second opinion. I think I have down the basic ways to optimize joints for low poly characters (either 2 edge loops or the 2 edge loops with half merged for joints). For ball-joints, I’m still not quite sure what to do. Also, saw this thing here:

Is there anything that can autorig like this in Blender? Of course Mixamo isn’t perfect, but I gotta say, that could be a REAL timesaver, as rigging has been the most frustrating thing I’ve done yet, so much manual time spent weight painting and all. Then again, I could probably be doing things the hard way.