It's something of a special case within Trek:
1) Klingons were always different. Even in TOS, the one thing that characterized the Klingons was "Hey, they're different from the last time!". They behaved different, they looked different.
2) Klingon tech paraphernalia, OTOH, was bottom of the barrel. They got one ship in TOS, and one in ST3, but then were stuck with that for literally centuries. Accompanying both ships was a sidearm design, and the latter one again stuck for centuries. It was difficult to see any aesthetics connection between Exhibit A and Exhibit B there.
Two new designs emerged in TNG, the Vor'Cha and the Negh'Var/Voodieh, and those kind of had a common design ethos. But a shuttle was done on the cheap, not matching that ethos. Romulans got new stuff that, while not all that plentiful, was very nicely in line with whatever had been previously introduced for the era. Cardassians grew into an impressive theme park. Even the Ferengi thrived.
Then comes ENT, and the Klingon stagnation is extended backwards by another century. Vulcans and Andorians get fleshed out with ships, sets, props, costuming etc. Klingons are stuck, and due an overhaul. Thankfully, they get a range of CGI-kitbashed ships at least.
We have a discrepancy there, then: Klingon faces are defined by change, but their culture looks monobloc. How come? Well, it's time we learn that the latter looks deceive. (Or that change prompts racist conformity within the Empire, with the fortunes favoring different faces at different times, or whatever.)
I'm still thinking this is an opportunity, not just existing but also being taken here, even if it's originally just a very stupid idea that stuck for production reasons. And the way to remedy it is trivially obvious and trivially cheap: just insert a smidgen of the familiar, at your leisure, and both the desired diversity and the desired continuity are served. So I'm not worried in the slightest. Let the folks innovate with their designs, and sort it out afterwards.
Timo Saloniemi
P.S. digging the Vulcan courier ship a lot.