there's not much luck with hero matchups! this is why you scout with workers, so you always know what your opponent picked. item drops are luck based I guess and I'll admit to having raged a few times when my opponent got healing wards and I got ring of protection +2 or whatever, but in almost all of my games the person that I felt played better ended up winning.
the only hero I'm aware of that feels worth complaining about is the blademaster. guy is a douche. most other heroes are alright in my book. there's some heroes that become really powerful the higher they go (Warden gets really good at harassment with blink level 2 and fan of knives for example) but if you let your opponent creep up a hero you only have yourself to blame!