We sailed on the Volendam on their 94 day Grand Australia & New Zealand cruise. We loved the Volendam, and are booked on the same 42 day cruise you have booked, and the Pole-to-Pole cruise starting in January 2025 (133 days.)
I wouldn't be worried about it being like the Koningsdam. The crew was fantastic on our 94 day cruise. We had set time early dining, but decided not to do that on these upcoming cruises, as we thought the 5 PM early dining was too early.
We had breakfast in the MDR on the first morning of the cruise, and met several other nice couples that we got to know as the cruise went along. The rest of the time we had breakfast in the Lido buffet. Great omelets, eggs benedict and blueberry pancakes! And always made when you order - never sitting in a warming tray. We love this older, smaller ship - or as the captain would say every day at dinner time when he gave the daily update "the beautiful, elegant Volendam". Love that.