Great leaps happen.
DaVinci was wildly advanced of pretty much everybody else on the planet at the time he lived. I have a feeling that if you brought him into the modern world he would quickly leave us in the dust once he learned to use computers and gain access to modern materials.
We could end up with the DaVinci drive getting us to mars in a week.
I agree on all counts.. I think it is a matter of time when the following things happen:
1. We will find a planet like ours (uninhabited I hope)
2. I think we will achieve some form of Interstellar Travel.
In the next century we will have FTL..