None of it was new to me, but I'll put it this way. David Wallace-Wells' "The Uninhabitable Earth" or Kolbert's "The Sixth Extinction" (or hell, even "Desert") is better at articulating the consequences of global heating. Cesaire, Fanon, and Freire are better at explaining why dehumanization is both a necessary element for, and outcome of, violence and colonialization. Gorz, Latouche, and Illich are better at describing the economic, industrial, and social changes that need to be initiated to avert ecological collapse, and Kallis, Muraca, and especially Parrique have a better job in the last decade of consolidating those guys and presenting them under the broader banner of "degrowth." Kimmerer, Ocalan, Graeber, and Bookchin are far better at illustrating the links between ecology, reciprocity, solidarity, and the ethic of community versus domination. But none of those people were able to collect everybody else into one text as Hickel does in LIM.
As for "special ideas," again, there's nothing in it that isn't in other degrowth texts.The usual grab-bag is present: Ban advertising and manufactured obsolescence, shorter work week, campaign finance reform, wealth tax, debt jubilee, regenerative agriculture, more worker cooperatives. It's all very dependent on State power. Hickel seems to be under the assumption that popular political action can change the course of world governance, which, we're all on this site, so I guess I know what we think about that.
But it's still useful. For me, Path B IS direct democracy, reciprocity, sustainability, commons, decommodification, and solidarity, and the degrowth movement people are doing the best job of promoting that right now.