Non mirroring will hurt the design of our chart so it is not an option. Trying to use padding or margin did not work in our trials as it impacted the two columns and the result is that in one of the columns we completely lose the value (shown out of the chart).
I hoped you will have an elegant solution to the issue (such as a minimum height for the values) but I understand there is non.
Another question - we noticed many updates were done to the charts and we wish to know if now there is a way to set rounded corner for columns chart. For example you can look at the example sent (http://dojo.telerik.com/ocADa/3) - is there a way to have the two top corners of each column rounded?