Batch #2 was brewed during Thursday's snow storm. The ginger I used was much fresher than the ginger I had for batch #1, and I think it made a considerable difference. I ended up getting about 100g of ginger out of one medium-sized hand, compared to only 43g in my last batch. The hand was a lot plumper, so that was probably a big part of the increase in yield.
98g Fresh diced ginger
60g light brown sugar
60 g turbinado sugar
This was added to 8oz water and heated in the microwave to a boil. This was then covered with plastic wrap and allowed to steep for ~5.5 hours. I added this to the juice of 1 lime (juice only - no zest this time) in a 1-liter bottle, topped with ice water, and force carbonated at 30 PSI.
When I went to taste it the next day, it had gone flat. I'm thinking that the carb cap wasn't sealed too tight. I gave it a quick taste, and noted that the oversweet molasses character was still there. I resealed it and hit it pretty hard with the CO2. When I tasted it later that day, there was a nice prickly carbonation, and the oversweet character was gone. Note to self - carbonation seems to help counter that artificially sweet character.
The flavor balance was pretty much spot-on. I could taste enough of the lime to tell that this was where the acidity was coming from, but without too strong of a flavor to compete with the ginger. I could cut the lime juice down my maybe 25-30%, but it's ok at this level. The ginger flavor was nice, and there was just enough sweetness for balance.
The only thing that it needed more of is heat from the ginger. I got some spiciness on the lips and tongue, but it needs more kick for me. I really don't want to go up on the fresh ginger, because this recipe already scales up to a kilo of fresh, prepped ginger for a full 2.5 gallon batch. I've done some reading, and it seems that dried ginger is spicier than fresh ginger, although fresh just can't be beat for taste. I could try lengthening the steep time to an overnight steep, but I think I'm just going to add a tablespoon or two of dried ginger to the steep next time and see what that does.