The lasso selection shows a rectangular bounding box just around all the selected strokes. If the selected stroke is a) a dot or b) a more or less horizontal or vertical line, the bounding box becomes too thin to be useable. In fact, the bounding box has no center and therefore cannot be moved because all parts of the bounding box are now considered "edge" associated to scaling.
My proposal would be to define a minimum size for the resulting selection box. If it is below this size in X or Y direction, extend it. Alternatively, always leave a certrain margin around the selected strokes. Note that the resulting selection box is just a virtual object and does not directly correspond to the selected strokes (hence nothing else would be included in the selection).