Hello!
We can compare these adjectives to things related to the ocean as seen below.
As fast as a sailfish.
As big as a whale
As cute as a clownfish
As quiet as a starfish
As smart as a dolphin
As cool as a dive in the ocean
As cold as the deep ocean
As cool as a coral reef
As quick as a swordfish
As strong as a shark
For the bonus you could say a seashell is beautiful. As beautiful as a seashell.
I hope this helps!