The manual instructs to oil the hook, but nothing else. That seems odd, and I really love my machine. Do you think that's enough? What about all the moving parts inside? :?

I don't know about this machine, but many of the machines we have now are self lubricating. Many need oil on the hook. I think some also need grease which a repairman will do when a machine is serviced.
The Mega Quilter I know is semi industrial and it requires several places that are oiled.

I have a 230, and I only oil the hook. Everything else is taken care of during annual maintenance.

That is the only place that I oil it....but she goes to the Machine Spa every year....and the machine guru treats her to all sorts of grease ,oil and blasts of air.