Sorry to put on the Steam & Steel pimping hat again, but I want to discuss some of the things that Tzarevitch brings up.
Tzarevitch said:
We have hit on a slight sore point of mine so I will hijack the thread slightly. Honestly, I don't feel every new book that comes out needs to have a new rule for everything and hordes of new creatures that are slightly different from the existing ones. All that does is repeat the mistakes of 1e and 2e.
Except that there are lots of different concepts for steamwork automata and constructs that are not easily covered by slight modifications of existing constructs, as well as the fact that it's an opportunity to add some interesting new concepts in as well.
In terms of new rules for everything though - well, I'm not yet fully familiar with the contents of FFG's steampunk boom, but I thought that it *did* also provide new rules for steam technology equipment, does it not?
With regard to a lack of construction rules for steampunk devices, I am not sure why those are needed. They are just powered versions of ordinary items. Use the 3e construction rules, they aren't great but they work as well for steampunk stuff as for anything else. With regard to rules and stats for the items mentioned, a lot of these already exist as magical or non-steam-powered versions and don't really need new rules.
There are a lot of possible new pieces of equipment that are viable with the introduction of steam technology. Now of course many can be duplicated in some manner in the form of magical gear, but this doesn't mean they're going to work in anywhere near the same manner.
OTOH, I agree that you don't need to create some entirely seperate system from the existing D&D rules for item creation. The Craft skill performs a good basis of it. Nonetheless, people may want further details and description, especially with the effects on item production that industrialisation can have.
For basic game purposes, a ship is a ship whether it is steam-powered or a sailing ship. The only difference is the steam plant and the screws or paddles as opposed to sails or magic. For the same reason construction rules are not needed to build a flying ship, only to ENCHANT one. The same is true for a horseless carriage, it is a carriage minus the horse and with the addition of an engine plant. It does not need new rules to make it.
There are massive differences between a steam-powered ship and a medieval-style sea vessel, and this includes in terms of basic game purposes. Same with other vehicles. There's a whole different load of considerations that need to be taken into account both in constructing such things (being able to take advantage of improved motive power for extra armour etc, among other things) and by those who make use of them (steam ships are less affected by the weather, you need to consider fuel consumption, you need mechanics to keep the engine in order).
Steam & Steel will provide new rules that basically make it easy for the DM to put together a vehicle that suits whatever needs he has. He wants a heavily-armoured steam train with arcane warding, it can be done. A lightly armoured and fast dirigible with a luxury interior? The same. By allocating costs to additional hit die, AC and other abilities, it is possible to custom design all sorts of vehicles.
To take as an example the Steam Wagon vehicle entry - this can be put together so that it is a horseless civilian carriage, or a heavily armoured 'steam tank'.
3e already had examples of artificial limbs. (As I recall there is one if Defenders of the Faith). They either function identically to the regular limb or provide some stat bonuses. Steampunk limbs would be the same but possibly bulkier and more mechanical-looking and with gears and pistons. It is also certainly possible to have additional attachments build for the arm but none of this requires new rules.
IIRC, the arm in Defenders was quite unbalancedly good

Anyway, Steam & Steel covers all sorts of steamwork prosthetics, from 'Thief'-style eyes to steel arms, in fact you can almost entirely replace someone's body with prosthetics though it's damn risky considering the usual primitive state of surgery. IF you like the idea of the mechanised Remade from China Mieville's book Perdido Street Station - well, you can make them with Steam & Steel.
And it's pretty damn important for someone witha steamwork arm to keep it well maintained and fuelled. For those who are more heavily augmented, well, failing to do so can mean death.
As for the templates, what templates are you looking for? Steampunk cyborgs can easily be created using half-golem template and the iron golem. Simply add gears and stuff for effect.
Steam & Steel has a Mechanised template that allows a DM to quickly create heavily augmented minion-type guys for baddies

It also has an all-purpose Steamwork Creature template that can be used with any pre-existing monster to make a machine version, including details for how their special attacks like elemental attacks, poisons and spell-like abilities change. It also has one other template
As for mechanical golems, again similar stuff already exists. I use the iron golem and remove its special immunities and vulnerabilities to magic. It isvulnerable to critical hits unlike normal golems because it does have vital points (gears, hoses pistons etc.). Reduce the CR and make it cheaper due to mass production of parts and voila. Clockwork Horrors and Automatons (all from existing 3e monster books) also are easily convertible to steampunk.
You can do much better than just modding an iron golem. What about small constructs like the various centurions from Morrowind? Spider ones, man-sized ones and big, heavy ones too. What about civil automata used for moving goods around factories, or a 'manservant' construct? What about earth-shaking, massive behemoths that can crush castle walls? And Steam & Steel also provides rules for the greater vulnerability steamwork constructs have due to their internal workings and gears.
As for the maps, I agree some of these would have been nice. However, most of the vehicles aren't really big enough to need them. The steam ships (and submersibles) are the only vehicles that really could use maps. Everyone knows what a traincar looks like and zepplin interiors are fairly small as well (especially compared to the lift-bag). (BTW you can find interior maps of the Hindenburg on the web.)
I agree here. Steam & Steel wont contain maps precisely because there';s no telling exactly what a ship or submersible will look like in any particular fantasy world. It's likely to vary from campaign to campaign, especially considering the system of creating vehicles that I wrote for Steam & Steel has so many possibilities for what the final thing could end up looking like.