m0useanswered grow question a year ago a lot of what determines bud size and density is in the plants genetics and how strong the lights are that you are using when growing.
I've had 4 different plants under the same lights and feeding regime and they all has different buds. some big, some small, some fluffy and some hard.
If you got your growing style locked in and the buds are not what your ideal is, maybe time for a new strain.
Few tips, ensure you are delivering around 40DLI to the plant so its got optional energy for bud production and make sure its got enough nutrients. To much can burn the leaves and it needs them for making energy and in turn buds.
Good Luck!