Hey Marcin,
Your dio looks good.
Like the other guys have pointed out, I it may be just a little too clean and uncluttered.
And if you look closely at David's photo, you'll notice that Polish tank crew wore their berets in a very "un-British manner".
Polish crews wore their berets pulled back and wore their unit or regimental insignia dead center of the beret and not over the left eye like most Commonwealth troops.
I've seen many photos of Polish crews wearing a mixture of berets and AFV helmets.
You could use some of Hornet's British tankcrew heads if you wanted to upgrade your figures.
Hornet has a number of headsets with different beret styles and AFV helmets.
Keep up the good work.
Cheers,
jjumbo