I thought there was consensus that graphs should start at 0 on the Y axis to avoid misinterpretation, but a quick google search shows that there's not total agreement on that.

So, I would like the option to make the graph zero-based, without forcing everyone else to agree. :)

For some stats (like "users online"), the graph may stay flat for hours at a time. Currently, prometheus will draw such a graph as blank, with a minimal Y range, and a single line at the baseline where it's effectively invisible.