Scott, you can backsweeten. You would need to add potasium sorbate, then wait 3-4 days then add your sweetener. I added both at the same time once and the yeast took back off. (14+% and dry) oops! I waited 4 days then added more juce to sweeten.
If you use welches raspberry you can sweeten then place your jug in the fridge until you drink it. (raspberry and cranberryare not a red wine) It is not the best way but it works if you are not going to age it. Cranberry is my wife's favorite.
Northen Winos, Thanks for the tip on the raisins. I usewelchesas a cheep way to learn what will happen if I add this or do that.