Review the HTML layout for the filters.
Use or not the searchtools layouts given by Joomla ?
My opinion is 'searchtools' is very complex and difficult to custom. Some Cook filters goes beyond the simple combo (ajax, ranges, dates, multiple searches possibles ...)
Creating our own filters layout file can be an option proposed in the builder. Because the native Joomla layout can be ugly / unconsistant for the filters Cook propose.