Hi Attila,
The renaming makes some sense, but now I've already released and documented the old name, which isn't much worse, so I think I'll decline on that patch.
About the default -- I still think a lot of people might be (intentionally or unintentionally) using ratios to fill float slots, so to me defaulting to T makes sense. People who care about precision can easily set the variable to NIL.
Best, Marijn