As a practical scrapbooker, I prefer simple uncluttered scrapbook layouts.
Most of my scrapbook pages have a solid background, three or four matted photos or elements that flow from upper left to lower right, with geometric borders, captions that work as titles and few embellishments. I buy lots of embellishments, but use a strategic few to avoid looking cluttered or fussy, From that simple formula, I have created many different scrapbook pages that do not look simple.
Some energetic photos and events, however just demand busier layouts. I have no formula for my busy pages; they are all different, but in general if I use a brightly patterned background scrapbook paper, I try to use double mats and fewer photos.
I have fun making these busy pages, but not too often.