Hmmm. Something to model...

Mostly Polygonal Models

(MODERATE)
grandfather clock - https://www.clocksandcuckooclocks.com...s/dnhhgfc2.jpg

(HARD)
humanoid face/head

Mostly Nurbs Models

(EASY)
Vase - https://www.asianart.com/randel/large/jizhou-vase.jpg

(HARD)
humanoid face/head

Misc.

(HARD)
grand piano - https://www.themaninthemoon.com/media/piano.jpg

(MODERATE)
Vase and Flowers - https://www.hallrichard.com/vase.jpg

(HARD)
Demon character - https://www.summoner2.com/picview.cfm?artwork=Demon-01

Lofting

(EASY)
Snake - https://www.gatorland.com/images/canebrake-snake.jpg

Lofting/curve rotation + poly or nurb modeling

(HARD)
Vase - https://www.motherlandnigeria.com/pictures/vase.jpg