Dear Muazzam,
I would say the two points you shared are invalid at all. Prius works with it's own strategy define/bulit with in it. Car decides itself when to engage engine or when to run on traction battery or both. So, driver should not be worry for it.
As far as fuel economy is concerned, it depends on multiple factors. One major factor is driving habits, tire size, air pressure, traction battery health and even load in the car. Hybrids are driven with different technique (pulse and glide. You may watch any video on youtube), one need to learn it.
Resale could be the issue for spoiled cars and second main factor is maintenance as it is maintained in major cities by qualified techs if required. It has two known faults rather I would say replacements, one is hybrid battery and second one is ABS.
P.S: I have owned swift, Vitz 2014, Corolla 2012 - 1.6 auto and currently own a 2011, 3rd gen Prius 1.8 which has proved to the best out of all cars till date. I have replaced it's hybrid battery and ABS unit.