Well I do have a tendency to make up recipes as I go along Donald,
My suggestion would be to use a cider yeast in preference to champagne.. it'll be lower in final ABV, won't strip the wine of flavour and will actually impart taste to the finished product.
I'm not keen myself, on the whole 'add a teaspoon of sugar for a sparkle finish' thing ad hoc.... winemaking is to personal taste after all.
I think you are on the right track, figure out what type of ginger beer you actually prefer, then work towards copying it.
Don't copy anything off the net..taste something that is close to what you aspire to, shut your eyes , keep tasting and write down the whole tasting experience.Then you will have a purpose.
once you have a purpose, it becomes your goal.
Allie