You can define you infrastructure as a code using Terraform and Ansible, and update and configure you Windows systems easily, all source code will be manage with github/bitbucket.
Terraform can be used to define and provision you network stack and Server stack by planing and applying templates and modules.
Windows EC2 instances can be setup using Terraform.
Ansible can be used to pick up the Windows ec2 instances and configure them using roles and playbooks.
Ansible AWX is a UI for controlling roles and playbooks and make it easy for one dashboard to control all tasks related to windows EC2 instances.
The following diagram explain the process.