This may have been one of Jackill's designs, but IIRC, it is predated by the first, less armed incarnation, the Joshua Class Command Cruiser
. Cygnus X1 has the original blueprints, supposedly by Shane Johnson
. While the publication date is unclear, I do recall getting this set at a con at least a year or two before the Jackills datasheets started producing the variants.
And yes, I always loved this brand of Excelsior-era variants on the original designs. I always felt they really worked, aesthetically.