in-ear, on-ear, over-ear?
folding?
long cord or short cord?
Corded or cordless?
Bluetooth?
noise cancelling?
Do you prefer a neutral or bassy sound?
There are plenty of headphones which give good sound quality at a reasonable price but which get passed over because they are 'just headphones' and not 'feature heavy' in the way some folk want these days.
cheers