You can now change SL to SV (or vice-versa) and also change your color preference on the Nissan website. Login to your account and a new link is there for doing so.
I believe that all preferences indicated in the pre-order are just to give Nissan a general idea of demand, and that you can still order whatever you like at the time of placing the firm order with the dealer.
I did a online chat just now and here is what Meg said. The level three charging stations and ports have not been standardized yet so we have determined that this charging port should only be available as an option. Once a standard is decided by the SAE (society of Automotive Engineers) then the port also be standard. The port will work with the stations install over the next year.