I'm not a fertilizer maven. I do the compost thing, and mulch thing, occasionally toss in rock phosphate, greensand, AACT when mood strikes me. I don't use manure. I plant in overcrowded polyculture beds. And I don't use chemicals.
My garden produces more than I can use and preserve, but I'm sure it has potential to do even better if I dedicated myself to such a goal.
I did notice improved growth and health from using HAY as mulch rather than straw. I didn't get overrun with weeds the way it's always been drilled into me: "STRAW NOT HAY"
Also, I mixed up container mix using two premium potting soil mixes containing compost and mycorrhizae, in addition to the usual compost, garden sill, and sand. I also added DR. EARTH's veg garden fertilizer which I got on sale. my container plants that were repotted using this particular mix grew 3 times the size they started with. So draw your own conclusions.
Oh, there's a "soil conditioner" I like called "Gardener's Gold Bumper Crop". I usually spread some of that in spring in addition to my own compost. One of the premium potting soil is made by the same company. I don't see these at big box stores but at independent nurseries and garden centers.