I would sum it up as, the UI has all the basic modeling tools presented in it.. "Specialty situational" tools are seperate. Dont think you are missing out if you dont have all the scripts ever made (The UI can do them anyway) They are just created to speedup/automate something for a specific task, that the UI already does.

There is nothing that any of those scripts do, that you cant do with a default, just purchased version of MoI.