I like the shot very much I particularly like the position of the (perhaps a bee fly). I suspect if you go to the RAW file and then to Photoshop, duplicate the image you could enhance the insect by increasing contrast and saturation (you could select the background then reverse the selection) then drag one image over the other and brush the enhanced insect into the original.
Kostas, this is a nice image but your title really makes it! It's perfect!
The whole thing looks a bit dark and soft so I think it could use some brightening and a contrast boost. The fiy could probably be brightened even further with extra attention given to the eyes.
A perfect title, Kostas, and I like the comp and soft colors. There are some good suggestions above so I won't repeat. For the purposes of ID, it would be nice to have additional looks at your insect, but the shape of the head and the (relatively) long antennae suggest to me that this is a bee rather than a fly. It looks like it is using its forelegs to wipe off the long proboscis. :)
This image made me laugh. :D That fly is actually diving int, with its front legs in perfect position. Good timing and capture. I won't add to above suggestions.