Well, I think that THE sharptooth from the first movie is a good addition, after all, he basically is the baddest one. What's this leader MADE out of? If he's worse than the original Sharptooth...that isn't good.
The one from V is also a good addition, mostly because he was the last menacing Sharptooth in the series.
The one from VIII seems to be all right. He seemed to be a bad Sharptooth.
The Spinosaurus is okay, mostly on how the Spinosaurus was one of the biggest carnivores to walk the earth. I may be wrong though. But I thnk that he's good.
Redclaw, Screech, and Thud? Hmmm, I don't know about them. They're said to be the baddest Sharpteeth around, but they just seem so stupid to me. Oh well, it's your decision.
That's my take, but since it's your story, it's your decision on whether these guys are in or not.