That's exactly what I was going to do with my vegetable garden. A lot of people on here say that it is best to lay the compost down in the fall before (something to do with bacteria?) But I don't have that option, since I only started my compost bin last fall. I plan on either doing it your way, or laying down the compost as soon as possible in the spring.

Anybody else have the answer? :)

Any nutrients those egg shells would have will not be converted by your soils bacteria for a couple of years and those in the coffee grounds may well not be available for a month or so, dependng on how active a Soil Food Web you do have. Whether putting compost in the planting hole is a good idea depends on your soil. A compacted clay soil could create a problem since water would tend to flow into that planting hole and would not drain out resulting in drowned plants. If your soil drains well and has adequate levels of organic matter then adding compost to the planting hole really will do little.

Adding the egg shells to the soil will take a while, but I would do it. I mix a little coffee into my soil and sprinkle it on top as part of my fertilizer, the majority goes to the compost bin.