I really like eidolon mod, I think it is a really great magic mod. Continue your great work.
Just a little thing, I thin k it would be better if the Magic Workbench will keep the inventory in the crafting slot and not giving all bgack to the player.

Why?
First, when a recipe is little complexe, it can be hard to remeber where goes all items (People already have bad time to 3x3 recipes, and your table add 4 more slots :D ). Anybody like the Tinker Crafting table, because it is possible to place the somes stuff for the craft and came back later to add the missing part...

For vanilla crafting tabel with JEI you can click on the + sign to placed items on the correct slot, but it is not possible with your's, so you abvsolutly have to remeber everithing. If you do a l;ittle misstake and the recipe doesn't work, you want to look back on JEI, you have to place back again all your items manually.