There's something so delightfully undramatic about it. No wallowing in the squalor of Spinner's End, no dramatic reclusive hermitage, no warding out the entire wizarding world... just a small, tidy flat somewhere more conducive to his tastes, and keeping to himself on the edge of two societies. So many post-war stories have larger-than-life dramas for Snape, and it's nice to see him dispense with all that nonsense.