Interstellar is a very intelligent science fiction that connects the dots between Gravity, Time, Astro-Science, Physics et al and weaves a pretty good concept for saving the mankind in future when the pollution and Nitrogen levels would reach unbearable levels.
The whole set of sequences in individual capacity have been very neatly done, but the director and the editor failed to keep the movie tight between these sequences.
The movie opens with a very farm like location owned by an agriculture enthusiast who has been a fighter pilot and an engineer and progresses on with him finding this ultra secret Area 59 sort location of Nasa and then him getting selected to lead a mission to find another habitat for human kind. But I felt that the director spent a bit too long a time to build the base that made movie a bit too slow in the first hour.
Post that a lot of plot and continuity was lost in the discussions that were stretched a bit too long than required and at times the characters breaking out due to emotional stress. I felt this was being a bit too much.
Another aspect that I felt should have been taken care of a bit more carefully was the aging of characters on earth and the aging of characters on the space mission. As from the way I understood, it would take them 14 months for touching the orbit of Saturn from where they get on to the far side of the galaxy / universe, and spending 1 hour on a planet that side would be around 7 years back on earth (relativity and time equation). But I failed to understand how Cooper's age went of to touch 124 while returning to earth and then how come his daughters' age went off way high that she was under medical supervision. It was a bit too far fetched point that I have not been able to weave. Per my calculation, the total time that passed from the time the mission started to the time when these guys were returning would have been anything around 50 years or so, meaning Cooper should have been close to 90 or maximum 100 and his daughter should have been at the max be in her 60s.
Overall a movie that has a very good story and script, but the Director and the editor failed to impress with their work.