I noticed another post about this -- http://wordpress.org/support/topic/plugin-exclude-pages-very-slow-performance-on-large-site-1500-pages?replies=6 -- but it is closed. So I wanted to add my two cents here:
I really like this plugin, but I am also finding it to be an issue for performance. My site is not even as large as the other poster's site; it's probably less than 100 pages. But, according to P3 Profiler, Exclude Pages is hogging a big chunk -- usually like 20-30%.
Wondering if the plugin author has considered any improvements for this?