I think that NEM and what all the Star Trek movies lack is a sympathetic villain. One badd ass guy/girl who the audience can secretly barrack for.
A good villain makes the hero seem better. By making Shinzon so pathetic it makes Picard look weak when he can't defeat him.
The same applies to the TOS and nuTrek movies as well. There was potential to have sympathy for Khan but it is ruined by all the senseless killing.
In one Star Trek movie I'd like there to be an anti-hero who the hero and the audience regrets their demise. I'm thinking female Romulan Commander or someone like Sran.