Lurks-no-More said:
This means giving Spelljammer a tone of its own. I'd go with the 16th-16th-century vibe of pirates, explorers and so on; this would mean adding firearms and cannons (with possibly alchemical and magical versions as well), and getting rid of catapults on ships.
This is a must. Agree 100% The idea of the party running through the halls of a spelljammer they just boarded and firing their pistols and rifles, then going to melee weapons like raipers and daggers is too cool.
[/quote] On the other hand, I'd emphasize the fantastic designs of the ships; more Mosquitos, fish-headed Merchantmen, Squidships and Nautiluses, and less longboats, caravels and other boring stuff that only existed because Spelljammer had to include a way for characters from established, non-Spelljamming worlds to get into the setting.[/quote]
I agree with this too. Spelljammers should have personalities and be interesting to look at.
To go with that, refurbishing the ships is a must. The first problem with the existing helm system is that it requires a wizard to power it, and it makes that wizard useless for much anything else. Thus, you either need a NPC to power the ship, or one player to bear the burden.
The second problem is that the helms are way too portable, and very expensive compared to the hull of the ship; this leads to people looting the helms and leaving the hulls behind. Make the motive power come from the structure of the ship, instead; now, if you win a battle against an enemy ship, you have to either leave the ship behind or figure out a way to bring it along, instead of just looting a chair. (Again, I think the easy portability of the helms exists so that you can find one in a dungeon, bolt it into a ship, and fly away.)
And while we're at it, let's ditch all the weird helms that existed to get around the very limited availability of arcane spellcasting in AD&D. I'm not saying that there shouldn't be various drive methods around, just that those shouldn't exist because of the inability of the rules to handle a dwarf wizard.
I think your heading the right direction here too. The ship should be a whole thing, not just helms. I would focus on taking the ship apart ruins many of those pieces. Helms have arcane "circutry" tha run through the ship.
With that said, I think that the adventuring party roles should be reexamined for spelljammer. Just as 4e parties are going to have combat and non-combat roles, characters should have spelljammer crew combat and non-combat roles. Those spelljammer roles should be well developed, streamlined and not tied to the classes. Each role should be fun, so when you plug into that role and are doing spelljammer combat or noncombat scenes all of the players are having fun and have choices to make.
An example of this could be as follows: various roles include helm navigation (moving the ship, evasive actions), captain (acts as leader/ support like a warlord with the jammer lending bonuses to the other roles and moving his support around), gunners (the strikers of the jammer), engineer (support and controller elements, plus heals the ship by doing repairs and managing damage control systems/ shields/ gravity etc).
Each of these roles can be reflected by skills and feats instead of class abilities. Perhaps some classes can attach into a role (like wizards being to cast spells through some kind of arcane enhancing cannon), but as a whole, any class can fit into any of these spelljammer roles. Then when ship to ship (or ships) combat occurs, everyone has something they are doing to have fun, work together and be involved in team efforts to make the ship get through the encounter in one piece.
Finally, I'd ruthlessly purge all the goofiness from the setting. Goofy is not the same as fun; most of the time, it isn't even funny in the long run. Thus for example, no wacky, goofy tinker gnomes (one of the worst aspects of Dragonlance, IMO) with cobbled-together ships powered by rubber bands and giant space hamsters; if you want to have gnomes, make them eccentric but competent engineers, more like Captain Nemo, Robur the Conqueror and so on.
Again 100% agree with you. Giant space hamsters are funny and silly. Painfully so. They ruin the setting, even though in an entertaining way.
On a side note, D&D can completely re-own (taking them back from WOW) the tinker gnomes (in a serious manner, instead of them being silly) in Spelljammer. That is 100% where the cool tinker gnome belongs. They can have a knack with weapons and contraptions used on the spelljammers and by their crew. Multishot Blackpowder guns (so reloads do not take from the action), grappling cannons to hook other ships, cutters for sawing through the sides of other ships, plus unusual inventions for exploring through the phlogiston and wild space.