There isn’t anything particularly controversial about expressing dissatisfaction with politicians, local or national. In fact, it seems to be the national sport. What other subjects did you have in mind?
N.B. The issur of ashon harah does not apply to issues that are public knowledge such as a politician’s stated positions on legislative or social matters. For instance, it is not LH to say that Senator X supports unpopular position “A” ( Boy!. These circumlocutions are awkward).