I know it's a bit old thread but I have only started my journey with Jake 2 months ago. I am not a big fan of sweet in general. I am also allergic to cocoa, so there is little I can do to vary the taste of my Jake light which is too sweet for me (I dilute it to more than 500mL but then it's too much volume for me for a single meal).
Did you ever consider some sour/fresh taste? I love lemons, mint, raspberry (without sugar added they are quite sour). However I have no clue how would the formula react to a low pH of lemons so I never tried (I eat my Jake mostly for breakfast when I am in hurry so no much time to improvise).
Basically, call me weird but I never use sugar and anything with it or with sweeteners give me a sick feeling. So after drinking Jake I have to gulp a big glass of water with lemon to overcome it.