To answer the question of if the sport needs dominant fighters:
Fans' alliances to fighters is a strange thing. Honestly, I got into AA cause he looks like a Beast, has vampire mouthguards, and I dug his aggressive style.
I think style makes fans, more than wins do.
I have a buddy who like Spencer Fisher because of his flying knee a long time ago, for example. People hop onto fighter's hype trains for very strange reasons. Being particularly dominant isn't necessary.
You know, the multitude of Matt Hughes and Chuck Liddell fans probably comes from the fact that they're pretty easy to relate to, and Hughes had his slams and wrestling strength. And Chuck has quite the striking highlight reel.
Look at Tim Sylvia. He was relatively dominant (by some standards) for a far piece. But I can't think of a single true fan of his, rather than the "pity fans" that pretend to like him, haha.
So, no, I don't think it's so important that single fighters emerge. All fighters have a certain ego about them that made them become a fighter in the first place, so there will be no shortage of appealing personalities.