Is it possible to have too much brand identity, or why do most Nomos watches look the same?

They use the same movement(alpha) in a lot of the designs you showed. This might restrict their ability to change the styles, such as having the small seconds. 

Nomos also has a specific minimalism Bauhaus look. Deviation could go away from that design language.

IMHO, yes it does constrain their design possibilities. However, I don't see that as a problem. People turn to them because of a particular style, the Bauhaus aesthetic. So that restriction may actually work in their favor. I looked up their history was was quiet impressed with their movement development. Sure, the usual games about modified ETA movements. But they really did move away from that and developed their own mechanics. 

I also have Nomos Metro Update. this is a little different from other Nomos. for a cheaper Bauhaus design, take a lot at Sternglass.

I like accuracy, my Nomos is +10 seconds a day.

Damn. At first glance I thought this was a thread to bash nomos. I was very excited for it until I kept reading. 
I find these watches soooooo boring. Everything looks so similar. Like I said in an earlier thread. I think mostly spy’s wear Nomos. Because the watch is so boring that nobody notices you. 
It’s a clear conspiracy between the CIA and the German watch manufacturers. I once heard that James Bond was supposed to wear a Nomos. But Q was so bored working on it that he couldn’t build it into a lightsaber. Pretty much sums up all I have to say about it. 

In Nomos's case, it is a bit of a problem, because the elements that make up their design are not really theirs, they pre-date the company. Nothing is stopping other manufacturers to use the same elements with tiny variations - as there's not a lot of room to express yourself. And then their watches look like Nomos's. That does not just apply to Chinese homages:

Here we have the DUFA Gropius, the Dugena Dessau, and the Stowa Antea.

I was just wearing my Chinese homage (Feice) yesterday! Hahaha.

As far as Dufa goes, they don't have any real design language at all. As far as I can tell, the watch brand was resurrected, and a good amount of their manufacturing occurs in China.

Here is my Dufa, which looks nothing like the one you posted.

You are right about Dufa, but many brands, even better respected ones, have no real overarching design language. For example, what is the design language of Certina? Even when we associate a certain style of watch with a brand, as in the cases of Junghans or Hamilton, we often find in their catalogues lots of stuff that is completely unrelated to their supposed design language.

I get your point that all of those white dials look similar, but I think Nomos is far from a one trick pony. The dial finishing on this Neomatik is amazing and the movement isn't half bad either. I'd be proud to add a Nomos to my collection.

I've heard different model names, even visited their website at one point, but it still feels dishonest to say that they make different watches. I guess they own that style at that price point, but I can't help but think that this is solely because nobody else wants it.

Nomos uses dial color to differentiate itself, IMO. 

The order you chose to present the watches was ideal because it shows a design progression.  The difference between the Tangente and the Ludwig is so slight as to be inconsequential.  

However, the difference between the Metro 38 and the Club is so massive that it would be near impossible to confuse them.  

If Nomos were to begin checking boxes by putting out a chronograph, and integrated bracelet, or a GMT, it would lose a bit of its identity as "Nomos".

i wouldn't say it's lazyness. it's still takes a lot of time to design these "little" changes. it's like they only have a small toolbox full of design elements and they manage to create very different watches. if you like a minimal style and you pay attention to the details, they do differ a lot.

Not so much IMHO, there is a baseline of common colors.

Well it's not like they claim to be the inventors of the small second's hand but I get your point. 

What I don't understand is why do they insist on reusing so much of their DNA in each model instead of picking some distinctive elements, such as color or case shape for example, and diversify their catalog.

I think that this is where we are in disagreement because I don't think they created very different watches. I think they created many variants of the same watch.

But that's the whole point I'm trying to make. I like my Ahoi neomatik. I think it's well made, has a good movement and has a very appealing design. What I don't understand is why this expertise wasn't used to make more varied watches.

I don't think this is inevitable because when I look at the Max Bill and the Chronoscope, I see two very different watches that share a lot of common design and both can't be mistaken for being anything but Junghans.

What I'm trying to say is that I convinced there is a reason why most Nomos look the same and it's not because Nomos doesn't have the technical expertise and engineering or because they are too stupid to realize the benefits of reaching to a wider audience. The fact that I'm unable to see this reason doesn't mean it doesn't exist and so I was curious to see if I could get some possible answers here.

I personally like to think that they keep to a similer design on purpose so that they add to the brand character. If they were to make something completely new it would take away from the personality that Nomos Caries. which is what I feel is a main selling point for them and why a lot of people including me love the brand 

On one hand, diversifying their line-up would always be good... on the other hand, there are so many times when I've loved a watch design except for one little thing that always happens to be something I hate or dislike. Having a bunch of similar-yet-different models might not be a terrible decision if you cater to a specific audience who like your general style.

Top down view of a white dialed watches from a lot brands aren't going to look a lot different.  Keep in mind that those watches all have very different case shapes/profiles.

But let's look at it a different way. You are in the market for a white dialed watch.  NOMOS is offering you 6 different versions here and let's add in a white dial Ahoi Neomatik for good measure. You now have 7 different watches in varying degrees of formality and technology (in house manual wounds, in house and below average slim autos, varying WR).  Do you want something dressy, you have the Ludwig or Orion. Do you want something smart/casual, you have the Tangente and Minimatik.  Do you like the look of the Tangente, but want something more robust? There is the Ahoi Neomatik with its 200m WR. Something more approaching a field watch, there is the Club with its simplified case construction and 100m WR (that looks awesome on a NATO btw). Something a bit more Avant Garde, hello Metro.

When companies offer you similar offerings like this, it allows one to better find the most perfect one for your tastes. I will almost never fault a company for offering more options. People here may think that these all look too much alike and I won't try to tell you they are wrong, but at the same time if you want to find the differences, they are there. Personally, even as a NOMOS fan, there are at least four of these that I have little to no interest in (Orion, Ludwig, Minimatik and the Club), so the fact that they have 7 "similar" looking watches doesn't bother me and there are all sorts of color options available to really differentiate further anyway.

IMO Nomos don’t look the same at all. 

Tangente - Metro - Tetra - Club - Orion all look different.

I would count Tangente, Ahoi, Ludwig to be the same model. In another brand, they could easily be one line just models from different years