That is a crap load of salt if it's for one bottle. And agave nectar is almost pure sugar, although more fructose than other types.
I make my sports drinks, but for a typical cycling bottle (the larger type that have the second hump up high) I use about 30g of maltodextrin, a couple 1/2g of sea salt and a 1/2g of "sodium free salt" (potassium). That gets dissolved in about 4/5 water and 1/5 Vitamin water for a little flavor. I make it up in a gallon jug so I have it for a while. It works out to a little over 100 calories per bottle.