Hi Frank,
I know this post is ten months old, but I just wanted to leave a brief comment to help anyone else that may come across this.
First thing’s first, I hope you have some kind of backup solution in place. For those interested in any easy backup solution using a WordPress plugin, there is XCloner which allows you to easily backup your database and all your website’s files.
I’m not sure why you have yet to install a caching plugin–I recommend W3. Following the recommended settings for each option in that plugin will give your site a nice edge and speed things up.
I hope you’re also optimizing your database regularly (for a site your size, at the very least once a week, but it would be even better if you could do it every day). You can do this programmatically or use a WordPress plugin like WP-DBManager. A repair may also be helpful every now and then depending on what kind of changes the site goes through.
Depending on the specifications of your two servers and internet speed, it may also be worthwhile to upgrade.
I hope this helped you or anyone else that may stumble upon this.
– Colton
