On the "tower strikes from gyroscopic action" thing I am assuming that that could be made to work with either direction of blade rotation: there's no magic from being in the Northern Hemisphere that favours one direction over the other?
Nothing to do with hemisphere. Everything to do with the direction of yaw vs. the direction of rotation.
When you exert force on the axle to move the axis of a spinning object, the motion reacting to that force is "carried along" with the rotation of the object and appears a quarter turn from the angle where the force was applied. When you yaw a spinning mill one way it tries to "nod its head to look down" and the other way to "look up". This is the gyroscopic effect.
This comes into play when you furl by yawing. Furling is more abrupt than unfurling and also happens when the mill is spinning faster, making the gyroscopic effect stronger. So you want it to "look up" during furling to avoid the blades striking the tower. You accept the weaker tendency to "look down" on unfurling as an unavoidable but limited nuisance.
This means, with the typical upwind mill (blades upwind of the tower and facing the wind), you want your blades rotating so that, on furling, the blades going down are the ones being pushed upwind (and thus farther from the tower as they go through the bottom of the rotation) by the yaw. If your furling is by the offset-rotor, tilted-tail-hinge method, it means you want the blades to be going down on the side toward the tower.
(Or just build enough tilt-back into the mill axis and/or put the blades far enough forward that this is a non-issue due to large tower-blade clearance.)