I have an AT 17 and 14, and a girlfriend :) She (my girlfriend) is 5'2" / 115 lbs. She has padded both boats, and likes them both, but is less enthusiastic about the 17, which is a high volume boat. I would discourage you from getting the AT17 based on this...but otherwise, it's a stellar touring boat.
I agree with what others are posting here about boat length, given your objectives, as well as the advice to think less about getting the boat on your rack and more about something that's safe, solid, and worthy.
I'm biased, but Pygmy is a great choice. Another option to consider is the Murrelet. 17 feet, 22" beam, with multiple deck options, two hulls to choose from, and two cockpit sizes.
The 4PD with the V2 hull and smaller cockpit would be a really versatile boat for you.
I've test paddled the Murrelet V2 and enjoyed it - it has lower initial stability that the Arctic Tern, but is stable, and the V2 hull provides good maneuverability for times that demand it...
Yes I too would suggest a sit on top. Something in the 13-14’ range. I can get more gear in and on my Malibu X-13 than with my Easky 15’. The X-13 is a real performer too.
Caution to you about cold water: dry suit minimum or even a shorty wet suit. Practice in cold water a re-entry, and do it 4-5 times until it’s easy. A swamped and loaded sit inside is a bi*ch to handle dry, so use dry bags that are well sealed. For stability, I prefer my sit on top vs my sit inside. Either one will do the job nicely in the 14’ range. Parting note: a sit on top is MUCH easier to re-enter in the event of a flip.