The
problems issues opportunities I found are:
Symmetry - the whole boat is totally symmetrical so forwards and backwards are equally easy (or difficult)
Sail control - the user, not the servo system

my sail rotates a little more than 180 degrees and hasn't reall got a "front"
Orientation - see the two points above (the person I built it for asked me to put the dragon head back on (and it would be easier if the sail had different colours front and back)
otherwise she does exactly what you would expect and hope for:
Accelerates well,
Slips thru the water with no wake
Causes discussion
Good pillaging boat

I aim to do about a one metre version by basically the same methods - this will be much more buoyant and stable and the dragon's teeth will be easier to carve
andrew