Q. Where I can set the setting for the number of projects that are viewed on one screen? I think it is set to 30 currently.

A. It's 'PageSize="30"' parameter in the ProjectList.aspx file.

You can also decrease the number of viewable projects on the Activities page (15 by default) to speed it up.
It's 'PageSize="15"' parameter in the TaskList.aspx file.