Depends on situation. If you're tracking a person across the forest floor, being able to better see (or smell) small changes in the environment might make sense for getting the bonus. On the other hand, if you're tracking someone in an urban environment by looking through security camera recordings, beast senses won't do anything.
The Track By Scent trapping is, in general, more powerful; sure, it's not giving you a numerical bonus - but without it, you've got no chance at tracking someone across, say, an empty parking lot, or in some other environment where they won't leave visible clues to their passage.