The phrase "all the more appalling" is correct and usable in written English.
It can be used to emphasize that something is even more shocking or disturbing than previously stated or expected.
Example: "The lack of action in the face of such suffering is all the more appalling given the resources available."
Alternatives: "even more shocking" or "particularly disturbing".
The smidgens of self-awareness that Taylor and Amanda exhibit make their destructive personal choices seem all the more appalling.
It is all the more appalling that the denial was based on innuendo and misconstructions of Mr. Kushner's critique of Israel's policies.
(His pursuit of revenge is thus rendered all the more appalling — an effective vehicle for condemning ludicrous codes of masculine "honor").
George Canellos, the co-director of the S.E.C.'s enforcement division, said in a statement that the city's conduct was "all the more appalling and unacceptable," because of the earlier problems.
Coates's two books show how twinned fears of crime and punishment can be mutually reinforcing: how the historic failure of the police to keep African-Americans safe from violence can make police excesses all the more appalling.
George Canellos, co-director of the S.E.C.'s enforcement unit, said in a statement that the city's conduct was "all the more appalling and unacceptable" because of the earlier problems.
Meanwhile the doubters cited chapter and verse, the more appalling the better.
To make the situation more appalling, those children who need treatment the most are the ones least likely to visit the dentist.
In between typing up appalling autobiographies of skiers with titles such as Downhill All the Way!, he cooks even more appalling "culinary adventures" made of otter chunks or smoked cat off the bone.
Both men tell their stories with the obligatory cool of exiles, which makes exotic details and appalling hurt all the more vivid.
The shock is at yet more appalling acts committed in the name of Islam.
