Can we get some kind of gas bottle that would allow us to set storage monitors/conversion monitors to display stored gases?

Tanks and Gauge Droppers work on storage monitors - I can't figure out how to do fluids either on conversion monitors, this might be an inherent limitation (and it's certainly a doc bug) in AE2 itself.

You can right click with a gas container twice. Conversion might not be supported at all for non-items, but that would be a problem on the AE2 side.