Seed starting... soil balls?

I have had a significant uphill battle to start seeds since I started gardening.
First, I could not find a single seed starting soil mix near me that wasn’t miracle gro, so I tried using some “organic” potting soil mix that was really just a mixed bag of compost and wood chips. This didn’t work in cell trays because of the wood chips so I gave up.
Second, I tried making my own potting mix and using it in cell trays, but again had significant failure.
Third, I tried direct seeding and it works for squash and beans, but for some reason it didn’t work well for beets, turnips, or brassicas.
A few months ago, I heard about soil blocks by Eliot Coleman and I was intrigued by the idea but didn’t want to buy another piece of equipment that was just going to fail on me. So I used, and modified, Eliot’s soil block recipe and used 3 parts peat, 3 parts soil/compost from my chicken run, and 1 part sand. I mixed it all together with copious water and made little mud balls to seed into. A month or so into this experiment and I can say it works! There are random sprouts of weeds from the chicken run soil, but I can easily remove those.
Anybody else have some creative seed starting ideas?

I use equal parts coco-coir, worm castings and coarse playground sand in all my starter trays and have excellent results.
I water from the bottom in winter to prevent damping off, this time of year I just shower them daily.
  I have soil blockers but you have to get your soil mixes about perfect or they fall apart (or turn to stone). I start 100's not 1000's so my cell trays work for me just fine, then I up pot or plant in the ground when they get some true leaves.

My mix is about 60% dampened coir, 20% worm castings, 20% charcoal. I eyeball it, so those numbers aren't exact. I also add a sprinkling of mycorrhizal inoculant, and let everything sit together overnight.

I use cardboard TP tubes as starter pots. They're annoying to fill, but they work well.

I like the charcoal idea. I have dabbled in making some biochar and that might be the perfect way to add it to the garden a little bit at a time.

How do the tp tubes hold up with watering?

In the past, I have bought my seed starting mix at the dollar general.  I feel it has too much wood for my tiny seeds so I sift the wood out.  It would be okay for squash and watermelon.