I'm contemplating getting a kit. How many of you feel that the addition of certain additives... E.g. extra tannins or enzymes such as OptiRed, of extra oak, or raisins, etc, makes a better product? Do you just go with what the producer recommends? I like dry Spanish reds as a general rule, Rioja, Tempranillo. We have the grapes where I'm at but hoping to hone my craft a bit before next harvest. Thanks!