What you show sounds broadly normal for a very fast 24mm f/1.4 used wide open, especially near the edges. At f/1.4, lenses in this class often show flare/ghosting, coma, spherical aberration, and field curvature, and corner performance is usually the compromise—even on more expensive designs.

Your samples don’t clearly prove a remaining defect. Bright sodium lamps can exaggerate glow and odd shapes, and any filter or smudges on the front/rear elements can make flare worse. Remove protective filters and make sure the glass is clean before judging.

For astrophotography, the biggest improvement usually comes from technique rather than another repair: stop the lens down 1–2 stops, use longer tracked exposures if possible, and consider stacking. Many strong Milky Way images rely on tracking mounts and stacking, not just lens performance wide open.

So yes, this level of behavior at f/1.4 is generally acceptable unless you still see obvious one-sided decentering or much worse performance than comparable examples after careful testing.