here goes:
4 crops, 1 each of blaze, diamond, gold and iron. each is identical layout, surrounding a darkroom/cursed earth mob grinder in the middle.
A few people have noted that with magic crops, any form of automated farming yields only that crop types essence and seed drops, but none of the nature and weak essence drops. This one is automated, and it gets all drops.
In the back of each 9x8 crop, theres a row of dispensers with water buckets hooked up via rednet to a turtle running a simple floodgate control program. It acts like a button on the rednet wire, then sits for a few minutes to let the crops replant and grow, and repeat. Under each crop is 4 rows of lilypads of fertility, and all the dirt is fertilized dirt from random things. A planter takes care of the planting, and hoppers collect the drops when the water pops all the plants. The hoppers feed into a basic chest, then a bc wooden pipe + autarchic gate pulls the items, seeds get sorted out in a diamond pipe and sent back to the planter, everything else goes into an ender chest. ender chests are plugged into an AE system that automaticaly crafts the essence into their proper items.
Had this running for a few hours now and already looking at a few stacks of iron, gold, blaze rods and diamonds, and quite a bit of nature essence (somewhere close to 1k of it). Shortly I'll add more crops, I want to try making this autocraft lilypads of fertitlity and fertilized dirt, and I'm collecting mob essence from the grinder to eventually feed a mfr block breaker with fortune 3 when I start growing ores that need a fortune pick. I'm also playing with ExtraCells and the fluid components it adds to AE...im using it to store liquid mob essence and sludge, looking forward to what else I can do with it.