REPL is OK, work-spaces are much better, ala Smalltalk. The best analogy is like a SQL editor, you can simply write anything and execute it in place. The notion one needs to enter one line at a time, aka the REPL, is quaint; not something to really be desired except from languages that have neither.
REPLs don't have to be one line at a time. F# interactive and C# interactive work well with Visual Studio. And at worst, it's a simple UI issue. Like various SQL UIs, nothing stops a REPL from being a big textbox then letting you select text and "run".
Do Smalltalk workspaces do something fundamentally different?
Well, in Smalltalk everything everywhere is an execution environment; anywhere you can type, you can highlight and execute code. But it seems we have different definitions of REPL, to me a REPL is a command line; a textbox isn't a REPL, it's a workspace. Sure they're both code executions environments, but working with them is vastly different.
When using common lisp on SLIME you can type your code in the buffer, select it and have have it eval'ed. The result will be printed in the repl buffer instead of next to the cursor, but that's a pro to me.
When I tried out pharo I was pressing backspace all the time because outputs are not valid code and thus would break the highlighting.
Anyway, a repl is just that, a read eval print loop. If you interface with it using a command line or other means is just an implementation detail.