With developing the design for the EC-20, I considered using turboprops or Open Rotor engines as its power source but later switched to more conventional turbofans.
I agree that the vertical stabilizer came out looking far too small in area though one thing I can't quite gather is that the design came out looking 'squashed' in the photo, in real life the plan is rather longer than the photo shows.
For the Comet nose, I pretty much adapted that straight from that airliner (still my favorite) and adjusted the windshield to provide better wrap-around visibility for pilots. Only thing I'm not sure of is whether a modern compact Doppler weather radar would still fit within the contours of the nose.