For each 3.8 cu. ft bale, add 2-2.5 cups of dolomitic lime and 1/2 cu. ft. of pertlite. You don't really need the vermiculite.
6.2 pH to 6.3 pH is the correct ph zone of all waterings, with ferts or not.
I use Botanicare Pure Blend Pro veg and flower. Look at adding G.H. Floralicious too. Only other thing may be to add an enzyme, to help keep the roots healthy i.e. Z7 or Cannazyme or one of those.
Add enough perlite to the mix and it will never pack down. I like to go around the plants every week or so and stir up the top layer which will help it from packing. In four gallon pots, I water every 2-3 days depending on the size of the plants.
Lastly, especially when r.o. water is used- Cal/Mag will be necessary thru most of flowering.