Annep, have you tried Wasgij puzzles? I love them, and they hardly ever have blocks of boring sky, trees or water. The picture is not actually of the jigsaw, but of what the people in the jigsaw are looking at! There are lots of them, and I pick them up in car boot sales and charity shops for only a pound or two.
I always look for puzzles with lots of figures and action going on. A while ago I did a 3,000 pieces one, which took about 3 months in fits and starts, and covered my entire 6ft x 3ft table. It was a comic skating scene, with dozens of figures, and was quite a challenge.
My late husband used to sneak pieces into my puzzles, and my Mum used to finish them after I had gone to bed, much to my annoyance. I miss them both.