Sorry can't help as I've never heard of it.. if the grape is listed as lacking body and character.. it sounds like a blend of grapejuice and something else would be a good thing.. Have you considered buying a fruitbase kit such as those cans of blackberry concentrate or elderberry perhaps.. and coming up with a suitable combination of flavours to adjust it to your taste? I know you can also buy cans of concentrate in a varietal.. maybe add a can or two of cab sauv base to up the body and throw some more tannin and oak into the mix.
I'm not sure what your budget is, or how much freezer room you have. I see that raspberries.. blackberries and elderberries seem to grow wild for the picking over there.
To improve body in a fruit wine.. I use the juice of boiled bananas.. it will impart a smooth mouthfeel to your wine also. You can also add dark raisins.. and I have used dried dates too ( which I particularly liked when added to a berry based wine).
If you have free fruit.. experiment with it.. after all, the person that wrote 'rubired lacks body and character' may only enjoy complex, tannin heavy wines.. That may not be your preference... work with what you have.
Personally, I prefer to fiddle with ingredients.. it's a lot more interesting than kits.
Allie