All the discussion about the look of the Klingons changing, and no discussion of the fact that they had a complete culture transplant in TNG. How anyone can be okay with every change from TOS through the movies, TNG, DS9, Voyager, and Enterprise, and suddenly proclaim "The line must be drawn HERE!" Get real.
The artistic legacy the new Star Wars movies have to live up to is six movies. Star Trek's artistic legacy is something like 750 TV episodes and thirteen movies. There's a significant difference there.
You mean, other than that they always do? They changed during TOS, for crying out loud. The amount of makeup painted on, the eyebrows. The Klingons in ST V didn't look much like the Klingons in ST III, who didn't look much like the Klingons in ST TMP. Like the saying goes, change is the only constant.
If I never again have to see another hearty longhaired, leather-armoured guy laugh boisterously over his bloodwine and rokeg blood pie while loudly relating tales of great battles and the importance of honour, you know what? I'll be fine. Honestly.