Some more pictures
NX-0100 Mayflower, pretty much the same as the Kiray/Icharus except without the secondary hull, and with older looking engines. it's smaller than Kiray as well.
Starfleets first experiment with a round hull design. based on Johnnymuffintops design.
Here's some more pictures of the Icharus. It's engine was modified to make it match NX100 Mayflower more than the NX1600 Augusta. It's deflector dish was changed to a more traditional design as well