Started doing jumping exercises. Practicing landing and jumping onto things. I'm still doing strength training on the side, but have started running in intervals (ie: 30-60 seconds jogging, then walking for 30-60 seconds, then back to jogging..).
Also, my knee has finally gotten much better about getting "stuck". Before, if I had been sitting for 30 minutes or more, I would have to stretch it out a few times and it would be pretty stiff and wouldn't straighten all the way without some aching. But now, I can sit for awhile and it doesn't take much for me to walk immediately after sitting for some time. It's gradually getting better. And my flexion is almost completely painless. I work on my flexion by kneeling and then trying to sit down on my feet as far down as my knee will allow. It's gotten much better lately and I'm almost able to just sit down on my feet immediately without any prior stretching.