If you've reached B2 level, your pronunciation will probably be good. But there are still things that you might be able to improve, to sound more like a native speaker.
You can use sentence stress, intonation and connected speech to add more meaning and to speak faster. This podcast contains examples of how we use these features to speak more fluidly.
Please read the transcript as you listen; it contains more notes and some exercises.
TRANSCRIPT:
https://drive.google.com/open?id=1NHd8AkwPBjvMRA76WFucbBRoL5h6wr-u&usp=drive_fs