The majority of issues for the Charts module are for the D7 version, and I inherited them when I took over from @quicksketch. There are some great issues, many that have patches, but I don't have a great set-up for testing D7 issues, and creating and maintaining one is time-consuming. If you are a power-user of Charts 7.x, please let me know: I'd like to be in touch to have you review various patches before I commit them.