About the environment properties, makes sense. Although, I think it's a different issue from interactive value prompting.
While conditions and force are interesting features, you can achieve repeatable script executions by using batches which make a script an atomic action, i.e. everything in the script will be applied or rolled back.
The force in the suggested form (for operations especially) won't be implemented. For some commands, perhaps. In general, though, I, personally, don't like the idea... but I see your point. Conditions are interesting.