We are working on a seastead design.
This is NOT a normal boat hull shape, but it is a bit like a trimaran in that their are 3 floats.



Above the water there will be a big triangle frame, 80 feet on a side.
The triangle frame will be a sort of truss structure that also doubles as a 4 foot high railing to keep humans from falling off.
We will call the 3 points on the triangle "front", "left", and "right".
And the edge between left and right we will call "back".

At the same height and in the same style as the triangle-frame/railing will be a frame to support a rectangular living
area.  The this living area frame will be 14 feet wide and as close to the front as it can be 14 feet wide
inside the triangle.  It will extend all the way to the "back".   

The living area will be 8 feet height, with the bottom on top of the rectangular frame above.  Lots of windows in the
font and back and some along the side.    

There will be 3 floats/legs/wings that will be the buoyancy.
Each leg/wing will 19 feet long and have a NACA foil shape with 10 foot chord and 4 foot width.
This makes for a "small waterline area" similar like a small oil platform but one that can move through the water easier because of the foil shape.
Each of the 3 legs will be attached to the underside of the big triangle near one of the 3 points and going down into the water.
The 3 wings will all be parallel with the blunt or "leading edge of the wing" forward  so it is easy for the seastead to move forward.
Each leg will be 50% under the water (so 0.5 * 19 feet) and the top 50% out of the water.
On front of each leg on the top half that is out of the water will be a built in ladder.

Connecting to the bottom of the railing frame will be a netting like on some catamarans.
In the middle of the long side of the living area on both the left and right there will be a door and steps going down to the netting (about 4 feet down).

There will be 6 RIM drive thrusters, one on each side of the legs/wings about 3 feet up from the bottom.
These will be aimed so they can push water past the wing and toward the back of the seastead.

There will be solar on the top of the living area and also on fold down panels on the left and right sides.
In the picture have the fold down panels up and level with the top of the living area.  
The living area is 8 feet high and the fold down panels go out 8 feet.

Centered on the netting to the left side of the living area will be a 14 foot RIB boat with 1 outboard motor.   
On the triangle frame next to the boat will be a davit/crane for loading and unloading the boat.

The above design can do about 3 knots all day long on solar/battery.   It is already very stable
but I want to look at a possible way to use active stabilizers special for this design to make it even more so.

The stabilizers will looks like a little airplanes and go around the back of each main seastead leg.  
A small actuator will be able to make the tail on this airplane angle up or down so it can adjust the angle of 
attack of the main wing of this stabilizer airplane without the need of a large actuator.
While the thick part of the leg is 4 feet wide the back where the airplane will attach is very thin.  And to get the airplane's
center of lift to balance on the pivot only about notch into about 1/4 of the wing is needed.

What is the additional buoyancy force of an additional foot of water around one of these legs? 
If a stabilizer could reduce 6 inches from the top of a wave and 6 inches off the bottom then it 
could make a 4 foot wave feel about like a 3 foot wave, right?
How big a foil/wing would it take to cut 6 inches off a way peak or trough at 3 knots?
How much extra electricity would it take to keep moving at 3 knots with the additional drag from these 3 stabilizers? 
If we have 4000 watts already for the 6 RIM drives, what percentage on top of this would the extra power for the stabilizers represent?
If we make this out of marine aluminum about how much would you estimate it would cost for the airplane and the small actuator? 
What would it weigh in lbs?
With kites we might be able to go even faster than 5 knots.  In your aluminum design at what speed might we generate enough force to damage it?
If we need a stronger design, how much would it weigh and cost if we want it to be ok at 6 knots?
If the sun it out, or we are willing to drain our batteries, and we go 5 knots, how much could this wing take off the top and bottom of waves?
If this was an optional extra for the seastead how popular do you think it would be with customers?
When estimating costs assume a batch of 20 will be made in China.
Sometime a series of waves can make something with a resonant frequency near the wave period move much more than one wave
but an active stabilizer can really help get rid of this issue.

When the airplane stabilizer is moving through the water it can control the angle it is at but when the seastead is
at anchor and moving up and down there is may be a problem.  The pivot at the "wing center of lift" for the stabilizer
is 25% along the chord is in balance when moving.  However, when the seastead is stationary and bobbing up and down in the waves the 75% of the wing
on one side and 25% on the other will not balance.  So the stabilizer will rotate one way when the leg is going down 
and the other when the leg is going up.  It is not clear what the best way to deal with this problem is.  What do you recommend?