A couple of thoughts here:
Fresh VC does pretty much take care of everything. Vermicompost is the only compost that goes in my mixes, no thermal type compost of any sort. Disclaimer: I DO use a good bit of Black Kow during the season as a top dress, not in the mix, but consider it more as a manure than a 'compost'. The worms love it.
Soil tests: Yeah, sorta, kinda, but I agree more with the J. Benton Jones quote that HT has in his replys. A plant analysis is going to be MUCH more informative than any soil test IMO.
Also from HT: That vid pretty much backs up what I've yapped about for years concerning the bad rap that Dolomite lime got about too much % of Mg and causing problems. That SOIL study was done, IIRC, in the U.P. of Michigan which already has high levels of Mg. Good info if you're a Yooper farmer, but pretty much irrelevant AFA container mixes go. The only Mg in container mixes is what one adds, it's not native to the mix.
Wet