Hi Nikki,
I've just come across this post and thought I could add to your question 1 discussion.
Apart from all the best practices that are out there, from experience, I've found it beneficial to use your web browsers developer tools to emulate different resolutions and thus see what your dashboard looks like on multiple different devices and relevant resolutions. (WARNING: The emulation is not always correct. So it is merely to get a feel for what it looks like and how your page real estate is being used. If you emulate a different device, like an iPad for example, some functionality may not work as expected.)
Regards,
Matt