Hi CM, i'm Cyrus, a developer on the C#/VB IDE.
First: The benefit of this approach is that people can now use this sort of feature down-level. i.e. you can interoperate with this code even if you're on a previous version of C# or VB. Also, it means that the libraries can be rev'ed independently of compiler and IDE releases. There's a lot of value in having this sort of thing. And in the past people would rightfully complain about the lockstep nature of wanting to adopt a language feature, but having to switch over an entire toolchain to do so.
Second: We actually do have a feature to help you out here. It's available in C# in RTM and will be in VB in the next update. If you enable: Tools | Options | Text Editor | (C#/VB) | Advanced | 'Suggest usings for types in NuGet packages'
then we'll offer to add the NuGet package for this for you when you use a tuple.
We'd like to eventually make this option on by default. However, there is a memory cost to it, and we'll need to win back that memory usage in some way so that we can abide by our commitment to VS using less memory and being more lightweight by default than previous versions.