When we have multi-series bar charts, we tend to use stacked columns in order to save space and convey a total for the column. Understandably, stacked bar charts aren't possible with logarithmic scales, so we're presently stuck with multi-series side-by-side charts.
What would be nice would be a way, for charts using a logarithmic scale, to overlay each of the multi-series columns at a x-axis position so that space is conserved. I think ideally the overlay would be shifted slightly for each series so that each of the columns would be visible even if there were two columns with the same height. In addition, the columns should be sorted in order of y-value, with the largest column on the bottom and the smallest on the top.
Perhaps a 3D bar chart with a log scale would achieve similar results.
Thanks,
Arun