The side padding seems thin and might be inadequate to protect your components. Also, do they move around when packed? They should be padded at the sides and fit snugly - travel should be as minimal as possible.

You might want to put some filler in your SFF cases as well. Make sure that things inside can't really move even if they are not mounted. Don't know what heatsink you use, but that's one thing that's most likely to come off, particularly if it's using plastic clips. A flying heatsink inside the SFF would likely cause a good amount of damage.

P.S. I will be sure to avoid pelican cases in the future; from your description, they seem rather ill suited to the rigors of shipping.