One thing I REALLY miss about Sketch was the ability to select an Artboard and drag and drop the preview PNG from the bottom right corner.
Why - Because It made communication via Slack and other platforms much more easy. I could throw the concept together, grab, drag, drop, send.
With the current design, if I want to send someone a preview image I have to select the artboard, click export, select the destination location, select send, change screens, find my export, drag, drop, send.