If Bane was meant to be this "monster" throughout the film, being killed by a missile is perfect for a monster's death. And him being saved by Selina parallels Bane being saved by Talia like two minutes earlier.
The only thing I didn't care for is Selina's one-liner to top it off. That's the only thing I can say that hurt's the death. While others say it helps Selina's arc, there shouldn't be something that helps one's arc but hurt's another.