I wouldnt think of brining my wheeled photobag, it is 1. too large 2. too heavy 3. overkill for this trip. it is a car transportable case.
For Alaska, I am going to bring most of my stuff in a peakdesign everyday 30L. I usually pack my pd everyday sling too in my checked for day trips that dont require a full load, best camera bags for me. The backpack is a bit heavy, but really well thought out and protects my camera 100%.