raptorva,
One thing that keeps nagging me about your EC-20 is the size of the vertical tail.
Have a look at just about every existng twin-jet, big or small, with the engines under the wings.
While the area has come down a lot from the huge tail of the A300B to that of the A321 (as examples), you'll still see the area of the vertical tail is bigger than what you've drawn.
The "design case" that determines the minimum vertical tail and rudder surface is the case of an engine failure just after take-off, at which point the aircraft still has to be directionally stable, and controllable, with one engine pushing, and the other engine dragging....
The result, in nearly all cases, is a vertical tail that's a bit too large, but there's no way (yet) to get around that.
Oh, and one thing I really do like about your design is the "Comet" nose....
There must be little or no advantage in having a slightly "nicer-looking" nose, if you look at all the blunt noses that are all the fashion today (the piggy-eyed nose of the A380 really is the limit....).
But yours at least looks as if it wants to go somewhere!
CJ