New owner of a Yaris 2nd Gen D4D

[albi.ad8]

Hello everyone,
Got a Yaris 2nd Gen 4 months ago and it has the 1.4 diesel engine. As a person addicted to maintain my cars in top condition I wanted some advice on maintenance and preventative measures for know issues about this gen Yaris.
Car has 156k km and will replace engine oil and the respective filters (oil, fuel, cabin air and intake) and also the automatic transmission fluid.
In the coming months I intend to replace the front diff fluid and brake fluid as well.
Do you recommend anything else to be replaced?
Are there any common parts that are known to fail which I should be looking at? Are there any know water leaks which may ruin electronics (asking because I have even a Mercedes ML which is known to leak water through the tailights)?
What I have noticed is that the car has developed a wierd like a humming noise when steering left at hightway speed or when going in reverse. What can this be? I am uploading even a video about this noise)
Thank you in advance and have a good weekend.