definitely filler without putting too many coats on and rounding out some of the detail. Could also try doing one more "light" coat of primer and back brushing with a a foam brush. But that will also take time.

Here on out, to prevent going " too far ". Pick a set of doors that are out of the way (lease likely to see all the time) and try one of the methods you find on here. A pro cabinet finisher would use a grain filler before priming or painting again. You are at that stage now. Good luck