We all have to make some tough decisions when making larger SharePoint environments. One of the toughest is which SharePoint services shall be running on which server. We would like our servers to be busy at same levels, but it is difficult to find the correct formula most of the times. Microsoft has been running SharePoint on online servers for a few years so far and with currently over 20,000 databases over 19 databases across the world, its unlikely there is anyone better who knows which services work well together other than Microsoft.
MinRoles are predefined types of server roles that that will maximize the optimization of SharePoint workloads across the servers. The good thing about MinRoles is that you can select it at the point of installation and change at some scenarios even sometime after the provisioning. As it is the SharePoint Server 2016 Beta 2 which is the latest release available, there are six predefined MinRoles.