It was one of my most favorite concepts tsr ever came up with.
The problem is purist poo poo most things that don't come from classical fantasy, and spelljammer is a living example of defying that trope (see also the blackmoor, Expedition to the Barrier Peaks, etc).
It also suffers from being connective tissue in 2e rather then it's own setting.
So here's what I would do.
Personally I would have done it as a sort of babylon 5 setting.
Ultimately the Galaxy would split up into separate races that control different quadrants
- different crystal spheres floating through a philostein that mixes in different parts
- the flow is modified by ley lines (mana, divine, psionic) that causes different sphere to interact with each other.
- Starbeasts - used to block out routes between the crystal spheres
Key races include
illithid- the oldest of the space races
- setup psionic conduits to get what they want
- surprisingly civilized, yet can be callous and ruthless
- very powerful and alien.
- in spite of their coolness hostility to the other races, they appear to be dealing with something that terrifies them (with the understanding that virtually nothing terrifies illithids).
Dwarf- Their domains have wwII industrial feel. They have metal carriers and ironclads as well as strange magic to attract asteroids for resources.
- use press gangs/prisoners as labour but actually pay prisoners for quotas.
- They are also known for bottling outsiders and creating "demon missiles" to use on targets.
Elf- Like in the original, they are the British empire of the galaxy. Their butterfly ships are the most manoeuvrable in the known universe. They send out seeds that land and teraform sphere's to be more "elf-friendly" as well as use organic space mines to quarantine off their enemies. Their main Elfworld is embedded into a giant tree starbeast.
Orcs-They are effectively Klingon- like and obsessed with honor and dueling. They are also somewhat obsessed with eugenics and are slowly, but surely pulling themselves out of being cannon fodder by use of magical breeding/genetic manipulation. They also have become amazing at breeding magical beasts and often throw them at their targets before engaging with their well equiped troops.
They have two major, but different factions:
1 - The Celestial Kingdom
- A Chinese space kingdom from which all others get the "mandate of heaven"
- One of the oldest human kingdoms
- They use Feng Shui lines to manipulate magic and their ships.
2. The Imperial kingdom
- This space kingdom is Byzantium-like and a comparative new comer. They are bold, impressive and daring and are really upsetting the status quo as they seek out new info and bring it back to their wizard academy's.
Kobold- Space agrees with the little ankle biters. While not the biggest or the strongest, they have set themselves up as "honest brokers" and have become relentless in collecting stuff regarding their dragon legacy, and scavenging anything they can get. They often steal dragon eggs, raise the hatchling and then build their spelljammers around the dragon, acting as an outer shell, an environmental suit and weapons platform.
I might revisit once I've stewed on it a bit more, but tell me your thoughts on spelljammer. :)