I can add a description field to it. I'm not really for being able to change the type though. I'd rather have you delete the field and create one with the right type. The problem is that the type of field specifies how the data is stored. If you change the field type then it could create errors when reading the data as it'll expect a certain format. Unless you have a compelling reason to be able to change instead of delete/create new, I'd rather not put it all the check logic