There are far more important obstructions keeping us from the stars: the first being that to get there in less than a million years we would need to use up the entire Earth to provide fuel for our craft. But assuming we can solve the propulsion problem, stellar exploration will either be done by:

a) miniaturised robots with computer brains

b) human clones grown after landing (supervised by robots) from thawed fertilised embryos

Either of these is far more cost-effective than sending fully-grown human beings into space. And robots have the advantage of being far more robust: no air supply, no urine recycling and little or no terraforming would be needed. Their first job would be to set up a transmitter to send data back to us data on everything they see and do.