consider removing logins
Every semester, I required my environmental science college class to go to your website and browse through your biome maps to find their "home" biome. However, since you now require people to create an account, I have had to direct my students to other, lower quality maps elsewhere. I don't want them to have to spend 5 minutes creating a login just to use the site for few minutes and I certainly don't want them to all have to give up their email address. These are students, not data points.
If the purpose of your site providing information to the public, you're failing.