It occurred to me people might want the best of both worlds, so I went with a different option and added a property called ButtonsInsideBorder if this is set to true you get the new appearance, if it's set to false (or omitted as will be the case for older projects) you get the old appearance.
By default the property is false so when adding a new preset browser you will get the old appearance. I've also set the default of the EditButtonOffset property to 10.
If this sounds good to you guys I'll make a pull request.
With this new setting you can do things like this: