Wheiit first aired I thought that a Star Trek show that didn't have a ship or a Captain was dumb. TNG was still on so I didn't pay it any attention. Then when TNG finished I started watching it (S3) and I was hooked. But, I always felt like DS9 was the "Jan Brady" or Trek at the time. It only had 1 season to be the only Trek on TV.
I know it sounds cliche', but I really think it was ahead of its time. If it had come in today's era of cable networks producing original programming focusing on heavily serialized stories it would rock. We're talking Breaking Bad/Walking Dead awesome.
And I do believe someone posted here a long time ago some data that showed that DS9's ratings were better than VOY's despite all that.