It's looking very good so far Marek. As the inside colour is dark, you can try a very thin wash, of thinned black or a darker grey, just around the framework, switch panels and so on. When this is dry, apply a slight dry brush of a slightly lighter grey, then another of even lighter grey. If you think you have done too much, then go over those affected areas with a darker shade.
You can also use a fine pencil around some of the framework of the fuselage, lightly, which will make it stand out when the fuselage halves are joined.
Your model should look very good when it's done, looking forward to more pics.
Terry.