Most charts with one single series do not need a legend. The series is already self-described by the chart title and the axes titles. Legends may be certainly useful in multi-series charts, where they help identify what each color represents.
This gorgeous styled theme for the Microsoft ASP.NET Chart Control comes in three parts: Bars, Areas and Shapes. Use the GradientSeries keyword, and filter for the MS ASP.NET Chart product eventually, to list all chart templates from this category.
Rings must have thin fixed width. These charts look like circles, and may be usually generated from Doughnut charts. Main challenge is most doughnuts expose the inner radius or some other property, and the width must be calculated (if possible).
Chart applications do not always support all types of charts, but many chart types can be emulated, with another supported chart and a specific algorithm. Our Emulated Charts blog category has topics with specific emulators.
Search for all templates with the BuiltinPatternPalette keyword. You will find at least two “Pattern Palettes for …” chart templates. They are all special templates, in the sense they showcase all our defined pattern palettes for a chart app.