It would be better protection to register each piece individually, but the $55 application fee is too much for me to do times 49 pieces. That's why I group the year's work into one application. It's better to do that than do nothing.
I keep reading articles, here or there, about work being appropriated by large companies, as if it's their own, but it's actually the hard work of an artist who might not see the infringement or understand how to stick up for them self.
I can not stress enough how important it is to register one's work. If you run into a copyright infringement problem, the official registration from the Copyright Office will be much more helpful than not having one.
It's reasonably easy to apply online. There is a learning curve doing it, but I figured it out again without pulling all my hair out, and I have thankfully checked it off my to-do list.