The thing is, this movie bothers me and I'm only half way through it. When you are SAHD, you watch movies when you can and sometimes that means spreading out a 2:49 movie over two or three days. As a dad, I can tell you there is no way I would leave my 10 year old daughter to go travel across the galaxy, especially if I thought there was a slim chance of coming back.
Technology in Interstellar only works as much as the plot needs it to work. Which is true in all movies, particularly sci-fi films, but it’s not supposed to feel like it.
I suppose we wouldn't have much of a movie if Cooper didn't leave but just the coincidences bother me. He happens to arrive at the local top-secret NASA headquarters just as they are almost ready to launch and they hand him the keys to the ship because he's the best pilot around. He hasn't flown in years, let alone ever flown a space ship outside a simulator. Maybe a few months of brushing up on flying are in order?