Stop misting your plants, it is unnecessary and you are only increasing the chances of mold attacking by doing so!
Your buds will not grow much anymore, they are nearly finished with only final ripening occurring at this stage.
Two of these plants are ready for harvest and will not require any feeding, just plain water for a final flush, and the one with lots of white pistils still may need one more feeding before beginning a flush and harvesting.
Doing some training on your next grow and keeping the canopy more even will mean you can leave your lights lower which will increase bud size, but for this grow, there is nothing you can do now to make these buds any denser or bigger.
Once the plants have 100% brown pistils, THC breaks down into CBD and CBN pretty rapidly, so I wouldn't wait too long before harvesting some of your plants. Photoperiod plants will offer much betteer yields by the way.
Hope this helps, Organoman.