Just back from an NCL cruise that got with 5 miles of Hubbard and travelled well within sight distance of Sawyer.
Both were absolutely spectacular but my votes goes to Tracy Arm. Being a professional landscape scientist, I was simply amazed at what I saw! The sheer walls of the Arm are quite incredible and the scale of topography ... i.e. sea level to towering peaks etc. ... was breathtaking.
Yes, the glaciers are "genetically" different but from a visitation point of view I'd pick Tracy Arm #1.
Finally, we were so blessed weather-wise in our cruise. Sunny, warm and with light seas.
Hope this helps!