Aspose for Cloud APIs do not offer view/edit and share with permissions features. You can convert all of your mentioned files, create watermark and sign PDFs at the moment. Signing other documents is in progress.
You can consider using Cloud APIs offered by our sister company GroupDocs http://groupdocs.com/ as they offer all of your desired features including view/edit and share with permissions.
You can also use conversion, watermark and sign features of Aspose for Cloud and view/edit and share features of GroupDocs.