Then I realized that in his work on Marvel's 2001: A Space Odyssey comic book series, Jack Kirby drew one the best representations of Spelljammer's Wildspace ever!
A Gnomish Spelljammer Sphere behind a massive worldship.
A possible representation of how someone using a spelljamming helm perceives wildspace.
Approaching a crystal sphere.
When someone first sits on a spelljamming helm, their mind adjusts to new vistas of perception.