I bought a PS-X7 at the weekend and need to give it a once-over as well. As said, the motors don’t generally need lubricating and as long as it runs at the right speed(s) and the touch sensitive buttons work fine, then you should be good to go.
The automatic mechanisms can get stiffer with age, so lubricating them is sometimes required but luckily Sony didn’t buy their grease from Garrard’s supplier, so it rarely turns to concrete, unlike on SP25s!
Engineers: fixing problems you didn't know you had in ways you don't understand.