One shipping related choice you may face is deciding when an order or maybe some of your product inventory should be shipped with UPS/FedEx Ground or with an LTL (less-than-truckload) freight carrier.
The issue is that at some point, usually as shipment weights increase to around 200 lbs. or so, the cost of shipping Ground becomes more expensive than LTL. Most online retailers who ship b2c are used to always shipping Ground (small package) and do not realize that LTL is a viable (and often cheaper) option for them too.
The point is to make sure you compare rates for Ground and LTL as the weight of a particular shipment increases to around 200 lbs.