I'll answer this, with caveats, and then cheat.
Charlotte Brontë - Villette (Insane book: Creativity, depression, loneliness, art, processed in modern, intimate, honest ways - w/ one of the more fascinating unreliable narrators - though Jane Eyre is more of a page turner if you want to ease your way into it. Depends on your preferences in general.)
Jane Austen - Persuasion (If you just want to start out on your Austen journey with laughs and comedy, Northanger Abbey)
George Eliot - Middlemarch (Big old book, I found it to be a breeze and sped through it in a few days the first time, some seem to think it heavy. Like one synopsis says - "explores nearly every subject of concern to modern life". A sweep through a society in transformation with incredible insight, a big gallery of characters/perspectives, lots of humour and some emotional punches. )
Depends on what you want, though. If you want really raw social realism go with The Tenant of Wildfell Hall. Wuthering Heights is the absolute opposite of stale period drama. If you're into the political stuff, working class issues, Elizabeth Gaskell is a natural choice. Poetry: Dickinson. George Sand. Etc.