Currently, when you use a logarithmic distribution for the gauge scale, the minor/middle ticks are positioned at equal spaces from one another. Add an API that allows you to position the minor/middle ticks using non exponential step. 

The visual elements generated for the GaugeRange objects are not cleared when you clear the Ranges collection of the scale. This happens if you call the Clear() method of the Ranges collection.

To work this around you can clear the ranges using the Remove() method instead of clear.

while (scale.Ranges.Count > 0)
{
    scale.Ranges.Remove(scale.Ranges.LastOrDefault());
}

As a workaround you need to use a ProportionalBrush mode instead.

Currently, when you serialize a gauge control (using the XamlWriter.Save() method), the values of the properties of type GaugeMeasure are not serialized properly. Instead of the measure value, the result from the ToString() method of the GaugeMeasure() class is serialized - Telerik.Windows.Controls.Gauge.GaugeMeasure.

The Visibility property of GaugeRange is not applied when it is set or bound in xaml

As a workaround if you set the Visibility in code after the range is loaded, the property's value is applied correctly.

If the numeric indicator is visualized on a large area (its container has large size), its segments are overlapping.

The gauge control will have new knob-like indicator.

It should be possible to specify origin of the bar indicator. For example, the radial scale is going from -10 to 10. In the current implementation bar indicator always starts at the minimum of the scale. We should have an ability to change origin of the bar indicator so that it starts at 0. I.e. if the value of the bar indicator was set to 5 then the bar should start at 0 and go to 5, currently is starts at -10 and goes to 5.

RangeList and TickList should support ability to set list of the arbitrary objects as ItemsSource and use ItemTemplate to create ranges and custom tick marks.