change/customise iphone (ios devices) backup location in itunes

iOS devices storage are getting larger and larger with iPhone now gets up to 256GB. However, looking back to our Macbook (pro) lineup, we are still staying at around 128 - 512GB range of storage choices.

To customise the backup to a location somewhere else (e.g. to a local network drive) seems not an option we can easily choose from in our iTunes manual... I don't even know if we can practically do so...

It doesn't make sense and practical anymore to use that backup function in the iTunes, though it seems the only way to backup everything on the iOS device (different from that of iCloud backup).

I think it is the time Apple should update the iTunes backup function or simply make iCloud back-up the ability to function the same.

I wonder if anybody has ever faced the same issue before?

Thomas