I think that the reality is, that it is difficult for ordinary people to definitely know which departments can take cuts better than others.
From my own point of view
I am wary of more cuts coming from justice, and HM Revenue and customs.
Justice is so important.
And HM Rev and Customs - I know a couple of peeople at local level who work in it, and there have already been lots of cuts. Plus in the news, it is being said, that so many cuts have been made, that they no longer have enough staff to chase everything.
Local Gov - I expect cuts can be made, but they seem lean/maybe understaffed now in my opinion.