Ho Tozmom,
Congratulations on your success! While there is certainly plenty of data out there that suggests the best way to schedule your workouts, ultimately, it is a matter of what works for the individual. I wouldn't change a thing unless (or until) you hit a sticking point.
At that point, you don't need the latest greatest fad or program, all you need to do is use interval training. Intervals are simply efforts that are impossible to maintain for a long period of time. An easy way to understand them is with running. Sprinting "can" burn a large number of calories but because you cannot sprint for a long time, it is better, calorie burn wise to run or jog long and slow. Intervals are sprints done during a jog so that you can have the calorie frying of sprints and the slow burn of the jog...the best of both worlds. So, you would jog along happily burning calories and then interject a sprint, and then return to a jog. These are very hard and stressful, so should be used sparingly at first.
You can use this training in nearly any exercise program or system. That said, in order to allow your muscles recovery time, it is generally accepted that you should allow one or two days rest between strength workouts (your stretch bands). So if you are going to train your entire body with them, do them every other day or three days per week. Many people like to split their strength training and do part of their body in one session and other parts another day. An easy split would be day1 upper body day2 lower body, day3 rest day4 upper body day4 lower body.
Since you are trying to lose weight, the best option is probably to use your bands in circuit training fashion and do it three days a week. Circuit training is done by working your entire body in one session but without rest between exercises. This way you get a cardio and strength workout in one. You can set up your circuit however you want but because it can be quite intense, most people begin with large bodyparts like legs, and progress to smaller body parts like forearms and calves.
You can do aerobics everyday.
Keep up the good work!