my idea actually requires orbital construction and docking. i would construct an orbital station which would be a "space dock" type deal first. then i would construct my ship in orbit and dock it with the space dock. the space dock will have pods for fuel tanks to go where i can fuel my interplanetary ship. i would then launch the crew into orbit and dock with the station and transfer the crew to the I.P. ship and send them on their way. when they get back i would transfer them back to the pod the launched in and splash down. by this time i would have launched more fuel into orbit and the I.P. ship could then be refueled and ready for its next mission. as for the details of my ship, huge cargo area for hab modules to leave on the planet setting up a small colony. then use the cargo area to send parts for another "space dock" to be built in orbit of the planet where it can be docked and refueled from there to reach further planets beyond and eventually outside the kerbol system.