MicroSD Card reader I have since I had to buy that USB Hub for my macbook
Pi 4 - yes need to obviously buy
Metal Passive case - is it is one you suggest few posts back? If this case is used, does it mean no need of heatsink?
The case you listed is Rs. 1300. Is it really worth it? As even official case is under Rs. 500.
Official Pi Charger - Is this needed or any 3rd party 3A charger with cable is also ok? I do have my iPad 20W charger which outputs 3A as per what is written but I still will need to buy a USB C to USB C cable.
HDMI Cable - If I want to run headless, is this even needed? Especially if I am going to use DietPi. I know the kit I linked has the cable but I am not sure If I will use it.
USB Keyboard - Do I need this if am not going to use screen and will setup and run headless. I don't have wireless keyboard for now but can borrow from neighbor.
32GB Class 10 MicroSD Card - The kit gives sandisk 16GB, will 16GB not suffice? Apart from loading the OS and running from MicroSD Card, what else is space on MicroSD card used for?