Not every lead actor is David Janssen or Roger More or Scott Bakula. Some are Jack Lord, David Boreanaz, or William Petersen. The bottom line is how you like their work. William Shatner's Kirk will never be surpassed for me. I don't give a flinging turd if he was a dick to the cast or not.
However, the lower level cast's constant harping on it for extended spotlight grabbing is annoying as hell. So are the "Walter Koenig ripped Shatner a new on on Raw Nerve" declarations. BS. I saw Raw Nerve and the two of them were very cordial and only slightly heated at times (it's also well known that Koenig dislikes confrontation and is generally reasonable in person). The most interesting part of the conversation was about Takei: George and Walter are NOT good friends, yet George made him his best man. Hmmm.
Note to lower tier Trek actors: get over it. Shatner doesn't start this crap, you do. He'd be more than happy to let you all fade into memory and ride his horses.