4. Virtual Tourism (virtual on-boarding members on to a real autonomous ship and have them experience the ship journey in realtime)
5. Relay Transmissions
... well may be couple of more.
On a fun note, you can sink all of those autonomous ships near polar caps and prevent / delay global warming side-effects such as polar melting (if you sink enough no. of ships to affect the tidal transfers that is). But I would not suggest it, as its a waste of money and ROI may be less.
If you start in the "less ROI" direction - there are many. For example, you can use these autonomous ships to mine and transfer Polar ICE in containers (may be even in melted form) to desert places (such as Dubai etc...). You cannot do that in real ships because, melted ICE is dangerous to humans on board the ship as they can be drowned inside the melted water.