It depends on what aspects of the game you value the most. Since the museum is one of my favorite parts of the game I always prioritize it but if you aren't as interested in filling the museum that's up to you. Overall though, I wouldn't say donating to the museum is too much work. Completing it may take a lot of time, but if you donate the fish, bugs, art, and fossils you happen to collect while playing it will get pretty full.