First thing - document every batch you make. As you just discovered, it’s hard to remember what you did months before; so alterations or corrections become a shot in the dark instead of a reasoned adjustment.
The general theory among cheesemakers is that excessive dryness is due to excessive acid development. The sharp flavor is also due to acid content. You mentioned that you were using a lot of culture, so backing off on that will help. Reducing the time you allow the curd to cook is also a good way to reduce acid. The higher temp causes the bacteria to reproduce at a higher rate, so shortening the time will help. One thing I do to increase the moisture of my cheese is to add additional cream to the milk. I run a gallon of raw milk through my cream separator, which yields about a pint of cream, and add this to my four gallon batch. It gives a nice “creamy” texture.
Another thought: how long did you age this cheese? Two months is sufficient for a Gouda, especially since Gouda is traditionally a mild flavored cheese.