Both my dss absolutely love the Ladybird books -
"Night Night Baby", "Hey Diddle Diddle", as well as, among others
"Fidgety Fish" by Ruth Galloway (Little Tiger Press)
"Whatever Next" by Jill Murphy (Campbell Books)
"Chamelion's Crazy Colours" by Nicola Grant and Michael Terry (Little Tiger Press)
"The Snail and the Whale" (which even brings a tear to my eye) by Julia Donaldson and Alex Scheffler (MacMillan)
3yr old ds1 has memorised them all and reads them to his yr old brother,
and there's an ABC picture book with rather surreal pictures but I don't have it to hand so couldn't tell you who it's by.