1. That TNF jacket is a tri-jacket. You don't need a tri-jacket because you already have a mid layer in the Atom LT. Plus, the Triclimate is on the bulky and heavy side, so PASS on it. Don't even consider it further.
2. That Burton jacket is a snowboard jacket, despite what any fashionista might tell you. It's baggy and not designed for tighter body movements of skiing (compared to boarding). Plus, those types of Burton jackets are functionally crap. They recycle the same pattern/features each year, put it on a new fabric, and call it the "new" model jacket. Then they tweak with with 2 minor pocket adjustments and call it "another new model". Garbage. Nobody in the know wears a jacket like that for skiing, if they have a choice. And you do. So get Burton out of your head completely. Don't even consider it further.
3. The Arcteryx Alpha SL is WAAAAAAAAY too thin for skiing. You'll trash it with one rogue branch or brushing up against your bindings. And your money then just went down the drain. Arc makes some amazing stuff (though Gore-Tex isn't the tops on my breathable hit list) but the Alpha is not what you need. They have plenty of other models that work better for skiing, so pick one. If you like the look then pick another one like it, but suited for skiing. The Alpha SL is not the one you need, trust us who own Arcteryx stuff. THE TRICK, HOWEVER, is that the other models fit differently. You need to figure out which will fit you best. It's about the FIT, not the looks. I suggest taking a very good look at the Arcteryx Sidewinder, Sabre, or Rush. They each fit a bit differently, so get the one that suits your body type. Sidewinder is more baggy overall, Sabre is tighter in the shoulders and more baggy at the bottom, Rush is more roomy in the shoulders and trim through the torso. Pick one, buy it, don't look back, and enjoy a top notch jacket for years to come.
And on a side note, yes, Arcteryx does contract to China for manufacturing. And yes, Westcomb does still manufacture in Canada. And yes, Westcomb makes some amazing jackets with eVent (which is more breathable than Gore-Tex). The problem is the FIT. It's all about the fit. Westcomb jackets fit more boxy and short than Arcteryx. Arcteryx are generally more trim. So if Westcomb fits you well, go for it!! If not, then pick something else. I had to sell my Westcomb after I lost 30 lbs. It fit when I was more doughy, but afterwards it was brutal and didn't fit for the new slimmer me.
Bottom line: get a shell that FITS you well for YOUR body type. There are many excellent jackets out there, but likely only a few that will fit you really well. Some manufacturers are known for different types of fits, so find the one that works for you and pull the trigger.