Mother's Finest and I are coming from a different perspective, those are not actually brands they are fertilizers that amend the soil, and are made by many companies, FF makes them too. Personally, I use Rabbit Hill Farm nonsolubles (kelp and alfalfa meal, and soft rock phosphate)... They are rated with different NPK values, for instance the kelp meal is 2-0-5, and the soft rock phosphate is 0-3-0...
Although, if you are looking specifically for soluble nutrients, I have used most of FF line, and they work, but they aren't organic, they organic based... I know some gardeners who use biobizz and that works well also. Maybe try Canna and their bio line in particular.
I also wouldn't recommend AN, they are a shit company imo.
You can also make great teas with kelp, alfalfa, stuff like that... maxicrop seaweed is also something I use, and I truly love it.