We're about to come out with a super fun new 400+ piece puzzle, Angie Rees' Precious Cargo:
Here's an early sneak peek at Tara's puzzle design for this (so sneak it doesn't even have the image printed on it yet!).
As you can see, it's got unique knob connectors, and will have a lot of fun themed whimsy pieces, should total slightly over 400 pieces.
Also, the pieces are slightly larger-than-usual (not huge, just a bit big), so it should be easier to work for elderly puzzlers and younger puzzlers: