Thanks for your input. Definitely some food for thought which is just what I was hoping for.
By heritage I was really thinking of re-editions by manufacturers of past lines - think Omega Seamaster ploprof.
An interesting thread and it is going to be exciting to see how the collection will evolve. I was about to reply after the 2 first posts, writing that you definitely should include some vintage in the collection, but I see that you have closed that gap with post 3.
6 watches isn't much for a themed collection, unless you stick to one brand or one type of watches, so my suggestions below is based on watches that can "speak for themselves". it is not a full list but hope fully it provides a little food for thoughts.
Vintage + tool
to me watches are mostly about vintage - from a time where precise time keeping was a result of craft man ship and technical solutions. Lets face it; the best time keeper I have is my iPhone loaded with an app that is connected to 4 ntp servers, which in turn are connected to atomic clocks. Further I like the idea that the watch served a real purpose; worn by a diver/pilot/soldier and used as a tool of the trade. It is a bit too easy to lead you down the military road in this category (thats where my own interest lies), but they for sure fit the bill for both vintage chronograph and divers. Vintage divers are maybe difficult to keep waterproof so it might not count for a diver in your list above. If not military, take a look at the vintage chronograps: Mathey Tissot type 20, Brietling Co-pilot, Universal Geneve Compax (Space and Nina Rindt), and the Omega Speedmaster of course. For the divers some vintage Doxa Sharkhunters, Aquastar Deepstar or anything that Cousteau wore and obviously there is the vintage Rolex path. Vintage without "tool" elements, are fast going to be dress watches and size below 38mm, which by todays standards feels small.
when I hear GMT I think of Rolex - either the Master or the Explorer. But with your choice of a Bremont I wonder if it is a signal of "the desire of having high quality without flashing it"? GMT could also be a Glycine Airman, which is very tool-ish and available in both vintage and contemporary, or maybe a Bulova Accutron Astronaut with a turning fork movement. the two last are true 24 hour watches btw.
I'm not sure what the heritage category covers. Is it homage, re-editions or both (or neither?).
Anyway there should be room for a simple black dialed watch be in all collections; e.g. IWC XI, Omega RAF '53, Smiths, or a homage to those.