Try wall crawls.. Get in a push up position with your feet on the wall (about at a 45 degree angle).. then walk yourself backwards so you are almost in a handstand, then walk back out to the pushup position. repeat multiple times. They're fun. Always mix up your workouts, try new things and do major lift that involve all muscles. No iso movements. You've lost a ton of weight which is a great accomplishment, now time to start building strength.
Also, buy a set of rings to workout on. You'll either thank me, or hate me after a workout
http://www.ringtraining.com/