Hello Dimitris,
Great build, very original concept. And just as in movies or books, things don't have to be 100% accurate in a diorama. At least that is my opinion. I see it more as 'art' than as 'fact'.
That said, however, I think some concepts can be taken to a next level with a little bit of research. Or help from fellows.
For instance: remarks about the '234' British marking, about cactii and species of palms in Libya or Egypt are true and can easily be checked. (No cactii, your palms are Asian, not African.)
That goes for the Libyan desert lakes and their vegetation and terrain as well. (Google for Ubari Lakes, or Mandara Lakes, and you will see what I mean... For instance, you'll see sand deserts, not rock deserts.)
But as said: there is such a thing as artistic licence.
Another thing though... What

parks his Kübelwagen in a spot like that!? And what boatsman is giving full throttle when he sees that? We're seconds from disaster here!
Sometimes you have to kill your darlings: I personally believe that without the KW the dio will look much better, with more focus, and also more 'realistic'...
Maybe I'm wrong, you decide.
Cheers!