[EPIC] Improved map defaults

[emmalu]

Context

We can improve some of the user's experience by default.

Issue

We should complete the following UI enhancements.

Acceptance-Criteria

These are the tasks that need to be completed or artifacts that need to be produced.

• Better visualization defaults #281
• Improve map height for static HTML export #247
• Add a layer control for toggling layer on/off #203

[kylebarron]

Closing with #330. It's not clear whether the layer control should be a default behavior in viz. That can be a separate discussion