I'm not sure what you are looking totally what you are looking for, but let me explain how one of my clients did this with their wholesale. For retail customers we have flat rate shipping. For wholesale customers we set up shipping based on weight- and did a base rate of xxx.xx for shipping and then every 1/2 lb adds on another $x.xx

You can also use conditional actions to set up shipping for wholesale- because a retail customer will purchase maybe 3 or 4 items- but a wholesale order that has to be shipped by pallet is obviously going to contain 100 or whatever items (significantly more than a normal retail order). You can set it up so that if X number or items are purchased or X weight or X dollar amount that is uses a different shipping rate quote/method