I've had bantams. They can be fun but the eggs are really small.
This might depend on the breed. Pebbles was a batam australorp. She laid a really good sized egg. Lottie, Wyandotte bantam, lays a tiny one when she lays. They're the only 2 I've had any experience with but Pebbles wasn't much smaller than a Campine's on a good day roughly the same size.
I was always surprised by the size of Pebble's eggs because, like you, my previous experience led to the expectation of a really small egg. It was not so. For me they were a great hard boiled egg size & wonderful for devilled eggs. Lottie's are pretty useless & she doesn't lay all that often.



