If you are going for the rides you will have a good time but as mentioned many shows and shops are closed.
As you said you have a SP, I would go into SDC and when the rides have satisfied and you get ready to shop go to town, honestly that's what I do. I have tried to balance the cost between opening a store or show that may not be full and just plain training your customers to ride the rides and bail. I hate to say that's my SDC method. They are inadvertently training people to come ride and leave. Ready to shop? leave. Ready to eat? leave.....it is not a smart plan. People don't want to go to an experience and be shut out of options. What do you think when you go to the mall and see closed stores?
Disney has learned that keeping customers captive allows them to squeeze every dime. SDC is missing the boat. They are also training us to use SDC like a 6 flags. I appreciate the fact they open early but they do this to make money not to serve the customer, at least it doesn't feel that way with empty stages and shops with signs that say closed. They are blind in their corporate minds to see the pattern they are creating. Or maybe its intentional? Shift to new format?
I will be there in March I will walk around look at the changes, ride the rides and after about 3 hours max bail and go into Branson. I frequently don't spend a dime on park. It was not that way in the past, I am afraid I am not the only one.