Crater Lake is amazing, to be sure!
Waldo is about half the size, and both are in similar surroundings in the Cascades range. Both have exceptionally clear water, in part because neither have inlet streams carrying organic debris. That makes for beautiful color, my Waldo drone footage was just after sunrise, stills showed an amazing sunset over the western shore.
Use of Crater Lake itself is heavily restricted… no swimming, no boating, I think they’ve discontinued the tour boat service. Like all popular national parks it is *heavily* used, but you can get away from the crowds on the hiking trails… and winter is incredible!
Both are must-see. Camping is very limited at CL, Waldo is one of the chain of the Cascade Lakes which are all in National Forest adjoining wilderness areas, lots of seasonal recreation!