The icons of running applications do not match the set Icon size in Panel Settings > Geometry but are 4px smaller which makes some of them blurry. To have clear looking 32px icons in the Task Bar the set Icon size has to be 36px which would blur the icons of the rest of your active Panel Applets. To get around this create additional panel(s) and have them collectively make a single continuous looking panel by adjusting the Alignment and Margin in Panel Settings > Geometry.