There's the repl, and then there's nREPL. I do like ghci, but I can't execute arbitrary chunks of Haskell directly from Vim.

This isn't a function of ghci or Haskell, that's an editor feature. If you want that kind of functionality than emacs is probably your best bet.

Though you can send arbitrary code blocks from vim using vim-slime.

[1] https://github.com/jpalardy/vim-slime

Though you can't execute arbitrary blocks of text in Haskell. Almost everything non-trivial will require adding a slew of "let"s, not all statements are available in GHCi, and state gets wiped on every reload.

When I first began developing Haskell, coming from Clojure, these issues drove me crazy. Nowadays I don't miss them too much and doubt that they're really such good features to begin with...

But it's decidedly false to claim that GHCi is as flexible as Clojure's repl. Nowadays, Clojure's repl would make me anxious. It reminds me a bit of people doing live code edits on a production server. You can't ever be quite sure what you get.