Hi,
Most of the answer for questions around "Power User" role can be found in portal.properties.
1) Power User role should not be removed.
# The standard system roles are: Administrator, Guest, Power User, and User.
# These roles cannot be removed or renamed.
#
system.roles=
2) Power User role required/not for private pages can be specified by below property
#
# Set this to true if users must have the Power User role to have private
# pages.
#
layout.user.private.layouts.power.user.required=false
3) Default user role on creation.
#
# Input a list of default role names separated by \n characters that are
# associated with newly created users.
#
admin.default.role.names=Power User\nUser
You should override all the properties in portal-ext.properties file.
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