Wouldn't an unreefed main in that kind of air give you one heckuva weather helm?
No. The weather helm comes from the degree of heel and amount of force on the sail(s). If you were flying the main only, you would probably not have heeled as much, but you probably wouldn't have been able to get as close to the wind (depending on the design of your rig and the aspect ratio of your main of course).
Hard to say without being there but generally, when you are racing in heavy weather you want a big crew - think five or six people on a 27 footer. You're going to need to let the mainsheet fly somewhat during the gusts and sheet her in quickly, but smoothly, hence that's one crew person's job, and if they're not in really great shape - you're going to have to swap them out every half hour or so.
Ditto the jib if you're flying a big one - although you're not going to be playing it as much. General rule of thumb. Set your lay line (course) to the mark and then trim the sails to get max speed on your course. When you get gusts you fly (loosen the sheets of) the main and the genny enough so that the boat does not veer off course, but maintains her heading. Every time you move that rudder away from the centreline of the boat, you are exerting a slight braking force on the forward motion. Avoid it. It has a much greater effect on your speed than you might think.
Use lots of crew and balance the boat with the sails (smooth and steady movements - not jerking the boom in and out)so that you can maintain course without the boat over on her ear. Better to let the main out a bit further than might seem optimal if it means you're going to sail flatter. You lose a lot of speed heeling excessively.
Also - if you are racing reefed, spend a lot of time wrapping up the reefed portion of the sail. Tuck it snugly along the boom, nice and smooth so that it's not catching wind or flapping. It plays havoc with your airflow over the sail.
Good Luck !