Plants are looking very well!
If you're thinking of changing nutrient lines I know the MegaCrop is both extremely cheap and effective. ManOGreen has a whole perfected autoflower/hydro feedchart worked out. Coco would probably work very well with it.
I am using the Jacks 3-2-1 line in coco. I like it very much and find it both inexpensive and easy to mix and use. The have programs for both RO water and tap water. You can even send them your water and they will recommend based on the analysis. Worth a look:
https://www.jacksnutrients.com/