I agree, it's tough to find not only like-minded individuals, but people who are also capable of building a relationship. I spent some time on OKCupid. I was looking to spend time with a woman (I fall along the bisexual spectrum, but haven't really explored it much. Was attempting to do so.) Like you, I was contacted by a few couples who wanted me to join them, and a bunch of guys who obviously never read my profile.
That said, some people do very well with OkCupid, but it seems that patience is a virtue. I personally found it taxing. I am one for whom there is no sexual attraction without connection, and while some wrote elegant profiles, I often found the actual conversation lacking. Decided if it was going to happen for me, it would happen more organically.
In other words, your experience is not unusual.