I can't think of anyone besides Anders Hejlsberg that has a better track record with programming language innovation. At least 3 different languages that have all been commercially successful.
One of his projects at Microsoft was J++ which is basically own-brand Java. Doubtless that's great material for learning to design C# but nobody is going to claim J++ was a success.
VM integration with host OS, J/Direct (P/Invoke), events, COM integration, WFC (Windows Forms).