Hi Robert,

I'm afraid there's no side-by-side comparison for any roles given the sheer number of capabilities and permissions that make up access rights.  At my last count there were around 600 capabilities (!!) so it would be tough to show all the default differences.

At a high level Site Managers have most of the access rights of a Site Admin, however they are limited on site, server and security configuration rights.  I've included a couple of screen shots below that might be of assistance.

I hope this helps!