Welcome to the forum, and congrats on the progress so far! 91 pounds is incredible.
In regards to stacking products with EC, I would also suggest forskolin. It's a great ingredient to add to any thermogenic stack that can help with body composition. It can be purchased as a solo ingredient, PES sells Forskolin-95 that would be a great add-on.
Adding yohimbine or alpha-yohimbine is also another common addition to the EC stack, but be sure to assess your stimulant tolerance first. Since yohimbine is a stimulant, adding it to ephedrine makes a heavy stimulant combination. As mentioned above, using TA-2 Max (alpha-yohimbine) may be a good solution that won't bring all of the high-stim side effects that regular yohimbine brings.
You also mention that you're only using EC 3-4 times per week - is there a reason for this? You may see better benefits if you take it on a more consistent basis. Taking breaks can be helpful, but ephedrine has been studied and most would agree that it does not need to be cycled.
Lastly, you mention that you do light weight training in addition to your cardio exercise. Would you be able to elaborate on what you do for your training? You may also be able to incorporate some different weight training techniques that could significantly improve your progress. Let us know!