I’ve just begun Roth’s Perlefter, a novel he abandoned several years before he died (a state I see as categorically different from a novel unfinished because of death…) So I can’t say if I will like it or not, but I already love this from the (apparently) unfinished first chapter: “Professor Tobias was the only man in our town with a top hat. As he had holes in his pockets he needed to wear such a hat. On his head he comfortably hid an inkwell and a feather. This had the disadvantage that he could not offer greetings to anyone.”
If you’re new to Roth, go for Rebellion or Hotel Savoy for early work with an absurdist bent, or Right and Left or Radetzky March for the later realism.