thank's for submitting your patch.
The real problem is that the FrameworkHelper overwrites the TextFormattingMode and the ClearTypeHint in some controls.
I don't know what the project owners think about this, but i think the FluentRibbon should just deliver a default value for those settings on the RibbonWindow level and leave everthing else to the default WPF inheritance.
Or we could choose the alternative and simply leave all TextOptions and RenderOptions settings as they are per default in WPF.
That way one only has to change those settings for the RibbonWindow as they are inherited by everything else.
I will ask the owners tommorrow, as i would like to know why they implemented it that way.
Even Visual Studio uses TextFormattingMode.Display for the whole UI. The only exception in Visual Studio is the code editor, which switches from Display to Ideal when the zoom is not equal to 100%.