Of course I never carry all that stuff... Depending on the mood, I pick the MM - most of the time fitted with the APO-Summicron 50mm. For landscapes, the M with either the Summicron 35 or 28mm would be a nice pick too. Portraits ? Summilux 50 or Summarit 75 would be the good answer. And of course any combination of the above. I use a very small bag allowing 1 camera and 2 lenses.
If I find a solution tomorrow to carry just a camera and a lens in any kind of flight bag, I would go ahead and take only that combo rather than having an extra (photo) bag to carry. But that magic flight bag doesn't exist yet !
The "all condition" optimum combo, unless you know that you need a specific lineup for a specific set of photos, is the M and the Summicron 35mm. No doubt you can do anything with these two.