> If you're talking about conversion rules, explicit cast from void* to T* makes more sense than implicit since it is a downcast.

Yes, but you also need to specify the type in C. ((void *)p)->foo only works in New B not in C.

> IMO these are a mistake

Forgetting to check bounds does always result in these problems in C, this is not specific to VLAs. I find them useful.

> Exceptions are problematic in their implementation

Ok, but that means to me having these in the language is only a downside.