Your question got me interested in reading up on the topic, but I have no personal experience with the Arctic Hawk that can help you. However, these are my conclusions (for what little they are worth).

1. To the extent that the Arctic Hawk is meant to be similar to the traditional skin-on-frame boat, it would not have had, and should not need, a skeg. (Impossible to put onto traditional skin-on-frame.)

2. The Arctic Hawk should be similar in the water to the Chesapeake 17LT. Both boats should weathercock in a cross wind (but even my Shearwater Sport does that). A skeg (particularly a retractable skeg) can apparently make paddling in a crosswind much easier.

3. If you don't think you spend much time in crosswinds or cross-waves, the skeg is an unnecessary complexity.

What little I know basically comes from paddling boats shorter than 15' and from reading this helpful article: https://paddling.com/learn/going-straight-rudder-or-skeg/   

My opinion has not changed since you asked in June.  If you ever paddle with big waves behind you, you will wish you had a skeg.  If you are certain that you never will paddle in those conditions, then no need.   https://www.clcboats.com/modules/forum/thread.php?quickname=5&id=44495

i built my arctic hawk initially without the skeg and then added the skeg after two seasons of paddling and was happy i did.

i found that even without rough water, if i had strong winds coming from certain directions, i was doing a lot of correcting strokes or leaning the boat to in lieu of correcting strokes.....and the skeg just made it very easy to trim the boat to be balanced without a lot of fuss.

over the time i owned it, i was just going out further with longer segments....and so what may have been tolerable out-of-trim for short intervals....was wearing me down as the distances and time got elongated.   my typical paddle when i decided to add it was continuous segments in excess of 60 minutes or  single legs greater than  4 to 5 miles.

fwiw...i highly recommend the skeg kit that superior kayak sells.  its a bit of an expense...but its top rate material (all glass) and bombproof and pretty easy to install.  i have never had it not perform.   i have made a skeg also from scratch....and while it did not cost a lot of money in materials, i was surprised about how much time i spent to get it all done.

h

  Thanks for the great advice. I have decided to add a Skeg. I am going with the plans from Nick Schafer. I had purchased them soon after completing my second Shearwater Sport. It does take a lot of time, especially sourcing all the hardware, but the satisfaction of keeping the overall cost down is worth it for me. If it makes a significant difference in handling, I may add a Skeg  to the three Kayaks that I have already built. 

   Just to correct a typo from my last post. The Skeg plans I am using is from Nick Schade of Guillmot Kayaks. This, I believe is the same as the kit sold by CLC.