I use what works at the time rather than any "rule". Most of the time I make my own starch if I am working with bias edges but sometimes I just iron straight of grain pieces. I change my needle when it starts to be dull ( you can hear it make a popping sound as it goes through fabric). I like to use Aurifil thread but sometimes colour is more important. I like Hobbs 80/20 batt but will use others if the price is good.
My one constant is my Bernina machine.