After seeing several of the videos and articles the Starcruiser looks fun, but not $6,000 (or even $4,809) worth of fun. I'd probably bite around $1,000, and start to give consideration around $1,500, for the voyage.
Random thoughts: Smart use of windows from the atrium into the bridge to see out the bridge windows to save money on atrium screens. The blue shrimp still look wrong. I could see Disney offering discounts on land and space, space and sea, or land, sea, and space package while not discounting the rack rate of the Starcruiser.
I could also see Disney cutting down the experience to a full day of activities without the overnight stay on select dates for a much lower price (though still not cheap). Check-in early, have breakfast, and a few story moments. Off to Batuu for several hours. Back to the ship late afternoon and into the evening for a dinner show, some more activities and story moments, and then the conclusion.