Welcome to the community, @Cynthia_C!
Your best option (and quite possibly the only other option available) would be to use On2Air: Schemas:
I agree that On2Air schemas is the best option. However, it is not the only option.
The first thing I recommend is turning off all the lines in the Base Schema settings except for linked relationships. It may reduce the number of connect lines enough for you to be able to rearrange the tables with no criss-crossing lines.
Another option to consider is my Field List extension with a premium license. It will not give you a visual representation directly. Instead, it creates a table of all the fields in your base. With a premium license and a bit of post-processing, you can see which fields are used to calculate which other fields, and then use filtered views and the Org Chart extension to chained dependencies.