As per my understanding, project requirement to push registry setting by group policy to all 200 computers. if I'm wrong please correct me.
In order to make plan, we need some basic information.
1. Registry setting is user based or computer based.
2. Registry setting needs to apply for all the user/computer or it needs to apply for set of group of users/computers.
3. If other group policies are already applied to users/computers then it needs to check the behavior of those GPOs.
4. We have to check Operating systems whether all operating systems are same version like windows 7/8/10.
5. If we have multiple flavor Operation system and all are exist in same OU then plan will be created accordingly.
Note: Always plan will be created according to configuration in environment to avoid impact. analysis is required to create plan.. Thanks !!