Extremely slow transitioning from dashboard to home page

I read through your FAQ and troubleshooting tips, all very good, thanks.

I have a couple of questions:
1. When is it appropriate to use the “delete cache”? I have been having my clients use it every time they update the website. Is this correct? This concerns me, because when the cache is deleted, the visitor gets a poor experience because of slow load times.
2. My client is doing all content maintenance, and has gotten extremely frustrated because it takes up to 30 seconds going from the WP dashboard to the home page.
3. Do you have a specific recommendation on the “type” of hosting that should be considered if I am going to continue to let my clients purchase hosting (I’m an affiliate for a hosting service and that has seemed to work for me.)?

website is http://www.ayresadventures.com

Thank you!

http://wordpress.org/extend/plugins/wp-super-cache/