Now that we have border controls (#30124 🎉) I took a little time to explore how we might apply some of the concepts outlined in #27331 to refine the UX here a bit.

Some of the suggestions can be implemented now, others will require underlying components that are yet to be built.

Here's a before / after, and a list of the changes:

• Rename panel to "Border"
• Removed repetitious "border" copy in labels
• Re-arranged controls to match css syntax, IE Width → Style → Color
• Use a segmented control for the style selector (or perhaps just a plain select, see Refine border style dropdown design #31333)
• Use a stepper input for the width control. This one may depend on whether we need to allow users to change the unit from px to em etc.
• Use the new color control for the color
• Re-purpose the proposed padding control for border radii (Allow longhand and shorthand properties in theme.json and block attributes #31641)