Thanks for some great suggestions. we will evaluate these and see if can be added to future releases.
To answer your question "At this point it is not possible to export/import to/from DVM to Excel" Currently there are only 2 ways to add values to DVM.
1. In JDeveloper at the time of creation of DVM in a SOA Project.
2. From SOA Composer once the DVM is already deployed, by manually editing the DVM to add or update any existing values.