There is a nice brief and superficial description of new Exchange 2016 architecture changes in comparison to Exchange 2013 by Ross Smith.
And his “Exchange Server Preferred Architecture” Ignite session follows right then.
This session reviews the preferred architecture for deploying Exchange Server. These principles apply to both Exchange Server 2013 and Exchange Server 2016 due later this year. Learn how the building block architecture is intended to be designed for your organization and the principles behind the recommendations. This session covers the new server architecture in detail. This session allows you to gain deep understanding of the Exchange Server 2013 and 2016 architecture and is a “must-attend” session to begin your own design.