When doing XAML development, some things are just so much easier to do in Blend for Visual Studio (formerly called Expression Blend). These usually lean towards the designery side of things, creating styles and templates, adding animations and visual states, etc. This being said, Blend had some real drawbacks. It could be slow, especially on large solutions. It didn’t support solution folders and your solution would show up as a flat tree structure. The XAML source editor didn’t provide as much functionality as was available in the Visual Studio editor. Source control wasn’t fully featured, and a few other things.
This has all changed with Blend for Visual Studio 2015. It is now based on the same shell as Visual Studio, even though it still runs as a separate application. This means it can take advantage of what Visual Studio provides out of the box instead of implementing its own thing for the features above, and provides parity with Visual Studio 2015. On top of this it still provides its own unique feature set to help with all of the things it was good at before. Kind of like a best of both worlds scenario. If you haven’t looked at Blend in a while, it’s a good time to take another look. It will make you a much more productive XAML developer.
Now that the Blend team can focus on providing features instead of spending time duplicating what Visual Studio provides, I look forward to seeing what they come up with in the future to make XAML development easier. If there are any features you specifically want to see, go to the UserVoice site for Blend here and let the team know: https://visualstudio.uservoice.com/forums/121579-visual-studio/category/90110-blend-for-visual-studio