Raised bed vegetable gardening

I've had these raised beds in the mountains for quite awhile now - about 6 years.  Here was a reflection about them. 

They were originally filled with commercial compost (from the Asheville Mulch Yard), a locally created compost with veggie waste from the WNC Farmer's Market probably mixed with manures and turned frequently to compost.  It was quite a light "compost" mix.

So over the years, I've added mushroom compost, "garden soil," Espoma organic fertilizer, Black Kow, Black Hen, Ace's cow manure compost, as well as leftover Epsom salts, liquified ancient calcium tablets, fish emulsion, etc.

So now I'm suddenly thinking about micronutrients -- geez, has all of this compost provided enough?

Why aren't my plants gigantic like the ones in the community gardens that I'm associated with?  Is it that I'm planting them too closely, or just that I'm harvesting baby leaves as soon as I can, and planting intensively?

Are we getting enough iodine in our vegetables,  I'm also questioning?  Do I need to add some sort of kelp mixture to my amendments?

Hrrmph.

We still have as many greens as we can eat right now, with lots of veggies to come, not to mention the giant leaves of the community garden veggies, too, purchased with farmstand credits or volunteer/plant donation perks.  Yikes.