We have done a lot of kayak sailing on all of our Hobies (many different models), however not on the PA 14. Actually all 8 hobies we have bought, we purchased the sailing kit along with every single boat, and have never taken a Hobie kayak out on to the water without a Hobie kayak sail strapped to the side of the boat (not even once), to us it's just part of the boat.
I just looked at the website for that 3.3 square meter sail from Star sails in Australia. Boy do I wish that had been available a few yrs ago.
That much sail on a revo 13 might be a little scary without the training wheels (Hobie side kicks kit).
We used to run the Hobie kayak sail which I think is around 1.9 sq meter (smallish), we also ran a combination jib/spinnaker.
But boy was it touchy, we could only use the big sail in really light steady air, and mostly downwind. You still get wet a lot (capsize, which is all part of kayak sailing).
On our bigger boat which was an Oasis the 1.9 meter hobie kayak sail was woefully to small, as I would suspect to be the same with the PA 14.
The PA 14 is way more stable than an Oasis or a Revo, the problem with both of those is they flip so fast it makes your head swim (literally lol). I suspect on the PA 14 you will have a little more warning, and like Tom said possibly lean out on the gunwale if you have to.
I definitely would not get the training wheels (Sidekicks), at least not right away. I would definitely try the 3.3 meter sail out without any AMA's first and see how it goes.
With a furlable sail you can always run it partially furled in heavier winds (just like we do on the Islands).
Your Mirage drive fins pointed down should be sufficient as a dagger board for most occasions, yea you will get a little slide slip, but you should still be able to climb upwind just fine, and if you pedal at the same time it's even better.
On Hobies, the Mirage drives and the sail work in combo. It's best to not pretend your a dang sunfish, if you want to sail that way get yourself a sunfish. Totally different universes.
If you find AMA's are neccessary ( which I don't expect), then there is another alternative that works very well (instead of AMA's), that's to take some PVC tubing fill it with lead shot (from scuba weight belts), Then suspend just under the boat. This makes the boat totally un-tippable (like the weighted keel on a monohull)
Something like this :
Just PVC caps on the end are fine, nothing fancy, it's a torpedo shape, which is the most efficient shape underwater, and creates almost no drag (small diameter/longer = better). I just let mine find it's own way when I pull on the beach, it's not like you can possibly hurt it. The Spectra string is incredibly strong, and all you should need.
Here is a pic of me sitting on the rail of our TI with a keel weight under the boat.
Shouldn't take a lot of weight to lower the center of gravity (that's basically what you are going).
Just some food for thought
One problem that will likely occur is the mast pocket on the Hobie kayaks is only strong enough to support the 1.9 sqm kayak sail. It will likely fail with a larger sail.
What I always do is re-enforce the mast holder on all my Hobie kayaks. I don't own a PA 14 so I don't know what it looks like inside, (you are on your own here, but the same concept should work) It's super easy to do and requires no skill.
and there are a couple options basic, and advanced.
Basic: Just get access to the inside of the hull and look at the mast holder mount (on most Hobies you can see it from the front hatch). What I do is just clean the area around the bottom of the hull where the mast base is with denatured alcohol, or if you can get it (rubber glue remover, which is Heptane (heptane melts Polyethylene (what your hull is made from)). then just spray a light coat of Krylon for plastics spray clear coat around the area (very light coat). Now just get some GE silicone out of a calk gun and bury the bottom in a pool of silicone, Doesn't have to be super thick, but the larger diameter you have the better (more surface area). If you want to get fancy you can flip the boat over and do the same to the inside top surface inside the hull.
Advanced: If you take a PVC cutting board (or any plastic), make about a 4-5" dia disk with a hole in the center (big enough to fit around the mast base), now cut that disk in half (so you can install it), then just gob a bunch of silicone over the area (just like above), then just squeeze the disk onto the top while it's still wet. ( you can now tow your car with your mast if you so desire (lol)).
I only use silicone because if you ever sell the boat you can always just peel it away and remove it, (though it takes a while to peel out of there).
Oh one more thing, On all of our 7/8" dia aluminum masts, if we didn't shove a fiberglass pultrusion up into the bottom of the mast a couple feet, they bent too easily (maximum point of stress it just above the mast holder).