In my humble opinion, ATC takes direct control over you with speed, height and routing instructions to reduce the number of variables that would otherwise come into play when a pilot conducts his own version of a standard STAR.
Yes there are many different ways to skin a cat and we inventive pilots just love to experiment with every variation...there are enough problems of standardization in our own airline let alone with every other International visiting airline,
ATC's job is to maintain safe traffic separation and satisfy a myriad of different parameters whilst getting you to land at a specific time and distance from other traffic.
Our job as pilots is to comply as accurately and quickly as possible with ATC instructions. That makes both ATC's job and our job easier.
If you don't like the way ATC do it, consider transferring from piloting to air traffic.