To be fair, he's been fairly gracious on twitter with his departure, I half-expected him to have some snide comments.
With regards to Hughes, he's done well with handling Arnotovic who previously had personal issues, and I believe Shaqiri did to a lesser extent, so if anyone can change Berahino then it's him. Having said that, it was quite telling last month when Berahino said he was depressed, I think what the Stoke fans probably don't grasp fully yet is that he's a fantastic player/athlete but it doesn't really matter because of his mentality.
It will be interesting to watch it unfold, he could recover his career, but with all bias aside I think he will struggle especially after missing so much football and development.