Love the little redcoat (Royal Marine version for ships perhaps?). For the ship… yeah it’s a low-detail model, but in a lot of ways that’s not a bad thing - makes it easy to get the basic shape right before you stretch it to make it larger & more detailed. Also, don’t forget that Stonehearth will (eventually) get proper bodies of water etc.
As far as the dimensions go, I’d say (just eyeballing it) that your model looks perfectly okay. I’d definitely want to scale it up so I can add in more detail though. The black and yellow banding is something specific to Nelson’s ships BTW, which the rest of the Royal Navy later adopted - it’s good for the Royal Navy, but you may want different colours for the Ascendancy / Raya’s Children / whatever.
What else… bit hard to tell, but the actual hull may want to be a bit thicker. Have a look at the pics for some of the Aubrey-Maturin books’ ships on this page:
http://www.ctbasses.com/misc/BruceTrinque
Especially HMS Surprise (these the books you’re reading BTW?). It looks like the cannons tended to be quite high up, or at least that there was more ship below the gun deck.
So, some thoughts on a sailing vessel mod…
1. Ship designs:
Rowboats and canoes will work as early game ships - say 6 people tops in a rowing boat, which means you can ferry people across small stretches of water, fish, and so on.
Scaling up, we can start with things like cogs (15-25m long, so 7.5-12.5 Stonehearth people), which had crews of perhaps 20 sailors. Not exactly the best sailing vessel, but they were used a fair bit in Medieval Europe. There’s also the option of Viking-style longboats.
If you want a Classical rather than Medieval European (or later) design, triremes and such are an obvious choice, but as galleys they were more manpower-intensive than sailing ships. However, even up until the 1500s and later, galleys were very dangerous warships - more dangerous in fact than the sailing ships of the era. It was only when you started getting big sailing ships with equally big ranks of cannons that the galley fell out of favour.
Scaling up further, we get things like schooners, which could be a fair bit longer than that, but which didn’t need enormous crews. They were apparently used as “motherships” for smaller fishing vessels. Could also be used for whaling in-game.
18th/19th Century warships are probably too big in most cases - even frigates had ~28 guns minimum for the Royal Navy - think 160+ft long and 100+ sailors. A ship like HMS Victory (104 guns, 70m long) would require ~850 people to run, which I’m guessing is the “game-crashing” end of the scale for Stonehearth 
. So, your HMS Surprise is probably the largest thing we’d want.
2. Infrastructure:
At the very least, we’ll want some kind of dock structure, so that you can easily get from land to ship and back. That means building out over impassable terrain, and possibly sinking supports into the water. Ideally you’d have some kind of dynamic design, with a variable length so that you could click & drag a dock out from a start point out into the sea. This kind of programming may make it into the game for bridges etc - otherwise give @RepeatPan a poke.
That just deals with getting to/from the ship though. Real ship construction requires either building it on the shore & floating it out on a high tide (something I doubt Stonehearth will have), or building it in a drydock… which means doors to let the water in, pumps to remove it, and so on.
Oh yes, ships are in many ways constructed like buildings, so you need to consider how the workers are going to build the ship too. If nothing else, they will have pathing requirements, scaffolding, and a means of carrying cannons & supplies onto the ship so they can plonk them down like they do with any other in-game object.
The other option for building ships is either magic (poof - it appears in the sea where you wanted it to), or it’s an object “placed” at the end of a docks, like a bed or fence gate is placed on a piece of land. Much less infrastructure-intensive, but it would look silly.
3. Sails:
My thought for sails would be to make a huge flat white voxel, but split it into thin strips. Then in 3D Studio Max (or whatever) you could move those strips to show a sail filled with wind etc. This is the method used by Radiant for the game’s models: each human is in fact made up of lots of smaller separate voxel models all placed in the same file, and then animated.
However, having someone who can use 3DSM for the animation work would… well it’d be useful 
. Off the top of my head, you’d want animations for the sails, cannons firing, cannonballs hitting, and huge (HUGE!) amounts of smoke. Maybe also a rocking ship animation and anchor-chain-dropping one too.
One more thing: the more expensive & rare an in-game object is, the more polygons you can throw at it, all things being equal. So to go back to your ship & my comments on frigates, you could in principle do a really detailed model & then scale it down in-game, because players won’t be seeing more than a handful of them on screen at once.
4. Ship Roles:
On the civilian side of things, we have transportation, fishing, whaling, and scouting. A fully equipped fishing schooner could probably keep your entire Stonehearth town fed (unless it’s really huge or something).
For the military, we have raiders, escorts and line of battle ships (plus transports I guess, but that can use repurposed civilian ships). As before, I don’t think anything much bigger than an age of sail frigate is feasible in the game (although I’d love to be wrong!), but if nothing else the sheer resource / manpower investment will make any kind of warship a rare thing.
5. Crew Sizes Etc:
If you want realism, you won’t be building (well, crewing) sailing vessels until you’ve got a few dozen civilians free (probably lots more). Upgrade several carpenters to shipwrights, harvest a metric f—ton of lumber, iron, food, cloth etc, and then when it’s finally built, make a whole load of regular workers into sailors, appoint one a captain, and send it off. Or you could just have one-man ships, because that way people might actually build several .
Another thing to consider here is pathing requirements on the ship itself. Do you want sailors up in the rigging, or disappearing into the cabins & holds? Or do they just hang around on deck & reach into the nearest barrel for food when they’re hungry?
6. Ship Controls:
Sailing purists will be upset, but I think the best way to control ships is just good old point-and-click movement like most RTS games. It should be fairly trivial to order them to turn broadside-on to an enemy when fighting (or not). Waypoints and other commands like “return to docks” or “fish this (huge) area” and “drop anchor” will be useful too.
You certainly could go for a very advanced model, with wind speed, tacking and all that, but it seems needlessly complicated to me.
Finally, age of sail combat was very slow paced, which should suit Stonehearth fine. A British crew could fire a broadside every 2-3 minutes, whilst the French & Spanish took twice as long on average… it might take you 90 minutes to defeat an enemy age of sail warship, and even then it probably wouldn’t sink or explode or whatever unless completely outclassed (ships were often captured back then if they were worth repairing or re-using). Boarding actions and armed crewmen in the crow’s nests etc are also possible, although boarding actions sound like a pathfinding nightmare.
What else… some Classical ships had artillery mounted on them, but were generally either filled with archers, used to ram, or used to board enemy ships.
7. Enemies:
Well, we have ghost ships like the Flying Dutchman, pirates and the like (could be pirates/ninjas/politicians or orcs & goblins), and things like fish people & giant squids.
Whew, well I think that’s enough for now . I’m more than happy to see my sailor model etc used in a mod like this. Here’s a link to the .qmo file:
