I advocated that my son not be afraid to take pitches that were tough to get good swings on early in the count.
The approach that worked best for him was to go to the plate with a 2-0 mentality. He would look fastball away since that is what you get about 75% of the time. If the pitcher left it over the plate swing away and take your best cut. But if it is at the edge or off the plate or he runs one in then take.
Bottom line try to eliminate options and focus on getting a specific pitch in a spot you are looking for. It helped that he was a good enough hitter that with 2 strikes he could expand, defend the plate and go the other way and be dangerous.
First ball/fastball is a reasonable approach as long as it is balanced with making sure it is a decent pitch to hit. Swinging at fastballs for the sake of swinging at a fastball is a bad idea IMO.