It would be a great shame to lose Juno. Much of NASA's greatest successes and science stories are about running these very literally far flung space probes and robots into extra, double super overtime and all the additional science and discoveries they make just by being there. For example: Without Juno, what is going to be there for the next Shoemaker/Levy 9 event? Last time, it was Galileo, and it had a crippled high gain antenna. Don't throw away a still perfectly good space probe on mission.