The real substance of the series, UT, was about Shinji's existential climb out of self hatred and self denial. Both Anno (ze writer/director) and Sartre (who just oozes over the second half of the series, especially episode 16 and the ending) were inclined to theatrics, and Shinji isn't any worse then the characters found in No Exit. If you had stuck with it you would have seen his character criticized in detail; he tries to deny his freedom to make choices by calling himself a coward and rendering himself helpless, so others have to choose for him, because he's terrified of being responsable for his actions; a walking example of bad faith. And his character does go somewhere. Admittedly it's not until the ending (when Anno finally does the right thing and throws out the nonsensical main plot) that these issues are fully presented, and then, then you see Shinji beginning to shift and change and learn. If you're not into existentialism or whatnot, then fine, but the series is about much more then "Shinji is an emo wuss".
The biggest question I have after seeing this trailer though, is are they going to make the plot make sense? And would be a good or bad thing? If it is better, then it might just draw attention away from the elements I just discussed above.