An important class of children's books is the concept book. Concept books help your child to develop a foundation of knowledge they will need when they learn other things. Common concept themes are ABC's, counting, colors, and opposites. There are a lot of them out there, and your child will likely pick a favorite or two for each.
What's Up, Duck?, by Tad Hills, is a great book for opposites. There are many of the usual pairs, but there are some that I think are kind of unique. The tricky thing is to create illustrations that make the meanings of the words on the page clear, and I think Hills does a good job.
For 'front' and 'back' the characters you may recognize from the Duck and Goose books look like their in a police line-up. 'Awake' and 'asleep' is particularly cute. Here's a tricky one: 'Heavy' shows Duck trying to lift Goose, while 'light' shows Grey Duck balancing a feather on his bill.
So when you're ready for opposites throw What's Up, Duck? on the stack.