Enterprise Vault Exchange archiving

Requirements as follows,

1. ALL Exchange messages are retrievable (either not deleted (legal hold) and/or journaled)),  AND
2. Individual Users can search and retrieve their own messages AND
3. An Administrator with designated permissions can search and retrieve all messages.

Based on my limited understanding,  Item 1 and 3 can be achieved with either legal hold or journaling plus e-discovery but achieving Item 2 is difficult.

Any feedback appreciated.