We too were on the Radiance this summer.
We were on the July 31 - August 7th southbound from Seward to Vancouver.
There were 4 of us (in 2 cabins): me, my 88 year old mother, my 30 year old daughter and 28 year old son in law.
Nice location, not far from the centrum elevators.
The size of the room and bathroom, as well as the balcony, are more than adequate.
There were two of us in the room and there was ample space and storage for everything (and then some).
Even the shower was fine with us.
I would definitely pick this category and this location again.