I am afraid rounding bars' corners is not supported in Kendo UI Chart at present, however this idea sounds good and I will suggest sending it as a feature request at our UserVoice portal
. This way the community would be able to vote and comment it and if the suggestion gains popularity we will consider it for future releases.
As for your other question - we are planning to introduce Annotations
) for the chart. Please note custom icons are not in our immediate plans, however I forwarded your request to the team and we will do our best to provide the discussed functionality as soon as possible.
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