Hehe, yeah its one of my stranger designs so far.
Yep, I've checked out lots of the next gen shuttle designs, such as "Spaceship one", which are designed to take three or four people in to space. the jet technology is not available yet to make the ultimate jet/shuttle hybrid, as it would need engines that turn from jets (air-breathers) to rockets (fuel burners), in mid flight. One idea has been to dump the air breather part and focus on making the rockets more economical.
The next gen jet/shuttle will prolly feature as a early unit such as the warrior, though its small size means it'll be used like a fighter plane (check the last few pages of the previous thread for fighterplane/private shuttle ideas).
I may actualy make the small solar sail unit a scout or guerilla unit in the final version, and make a bigger version with bigger, more complicated folding wings as an inter system ship, though I'm thinking of not having solarsail ships as intersystem ships because of the way people will use them is not realistic to how they work (and the fact that a solar sail ship is very slow, and would take the entire game to reach the nearest system.

A slow moving no resource unit would fit the bill better, and would require no upkeep, as its sails could also be fitted with solar panels, which could power the ship. Early on your number of cities is going to be limited, so having a unit that doesnt require upkeep can allow you to build up a large military, without lagging in science and trade. (it'd have to be quite weak in combat though, to make up for the advantage).