Did the extra water you added boil off? Extra water during fermentation will make the wine drier and more sour. I haven't tried boiling the rice, only steaming. I think the popular method is 1:2 ratio rice:water for boiling
I follow the package directions for cooking the rice. Add the rice to the water, bring it to a soft boil, turn down the heat, cover the pot, simmer for 20 min. I think that very little water is lost to boiling. All is absorbed into the rice.
I also think that pre-soaking the rice for an hour or two would add more water to the rice. I don't know how much. I stopped doing that.
The rice that I bought for my next batch says to add 1 1/2 cups water to one cup of rice. Still can't wrap my mind around why some jasmine rice packages call for almost 40% more water than others.