We did this cruise a few years ago and really enjoyed it. It is the only bigger ship (2,400 person – considered a mid-size ship) cruise we have taken to date but would take another Holland American cruise in the future based on the experience.
The nightlife you can take or leave --the ship is large enough that you can always find a quiet place to relax or go back to your cabin. FWIW we went to some of the evening shows on the large stage and found the jazz band enjoyable. They did not have classical music for our trip but you can see if that is an option some nights.
I’d recommend you get a set dinner time – it saves time waiting for a table at night.
We did spend a lovely couple of days in Vancouver prior to the cruise but did not go to Victoria.
Feel free to PM if you want more details.