Just chiming in to voice the same issues. Workspace performance is at times simply atrocious - what should take me 30 seconds to update has - for the last few days - taken 10 minutes EACH. I really love the flexibility of Analytics workspace, but it has to work reliably.
I hope that this is just temporary.
And a product enhancement suggestion:
When I select an arbitrary date range (e.g. two weeks from Dec 10 - Dec 23rd), adjust the 'Last Week' and 'Two Weeks ago' time ranges to automatically correspond to this timeframe. As it stands, '1 week ago' and other relative time ranges take today's date instead (which isn't what I want)
Thanks,
Chris