Hate to be negative here, but if you really want a single sail boat.... why don't you buy a single sail boat? No sloop rigged, lightweight, non keel, boat is going to perform well under main alone. First of all, the mast on single sail boats (cat rig) is place forward of the boat's pivot point so the sail can help the boat tack, sail up wind and balance the helm. With two sails, and the mast placed at the boat's pivot point, the sailor will use them to balance the helm, help push the bow to leeward when turning, and improve air flow over the main going upwind.
In your scenario, heeling the boat will not be an issue. That's easily controlled with sail trim... headsail, mainsail or both. What will be affected is you ability to turn upwind efficiently. You will find yourself "in irons" more than you want... especially in light air and a boat with no heavy keel to provide momentum. You'll also have trouble when it's choppy because there will be no headsail to push the bow through the short, slapping waves.
Weather helm can be an issue, but with fresh sails and a little mast tuning you might be able to control it.
Finally, if you must, sail with jib only.... maybe invest in a larger headsail with roller furling. Or start looking for some cat rigged 17 footers... there are plenty out there and great fun to sail.
How cool is this 15 footer? (sorry, it's sold)