haha, you are doing the same thing I did. So all the connections are actually related to the Onion cloud.
you can stop the service and you will see the connections slowly disconnect and remove. If you reboot, the service will come back online. I deleted the service completely as I didn't want / need the Onion cloud.
service device-client stop
opkg remove device-client
After the reboot you shouldn't see the connections anymore. I actually removed most of the services pre-installed on the Onion.