re: Looking for a way to show all entries on the main page. I have 181 entries and currently the main directory page shows 20 per page and 10 pages.
Which template are you using? All templates but cMap you would use the
page_limit limit shortcode option, like so
page_limit=50 or disable pagination with
If you are using cMap, you can use the Template Customizer to change the pagination settings (you can use the shortcodes if you wish, but the customizer is preferred).
I very highly recommend display that many entries at once. It’ll make the page load much more slowly. This is not a bug or limitation in Connections. The same would happen if you tried to display that many WordPress posts on a single page. Depending on your server/web host, I would recommend more than 50–100. You could try it and see if the load time is acceptable to you.
re: since the Search feature works against the whole dataset, is there a way to make the Sort of a given field work against the whole data set?
Not sure I really understand the question. You can change the default sort order field. I think that is what you are asking. See the doc page for the order_by shortcode option.
Hope that helps!