Here is how businesses set up a default profile on Windows, and how this may help you, but I'll try to explain the caveats as well.
You said you already have an account set up just the way you want. For the sake of explanation, I will call this account the master account. Browse to the C:\Users folder on your PC. In Windows Explorer, go to the view tab and check the box to show Hidden Items.
Find the folder for the user that you want to become your new default. Make a copy of that folder. There will be a hidden folder called Default. Rename that folder to Default.old. Change the Copy of Master folder to Default.
Now, any new user you create on this PC will use the Default profile that you have customized to your liking. However, this won't affect users that are already on this PC. If you want this to apply to users who are already on the PC, you will have to delete these profiles off the PC. Go to the control panel and search for "Profile", and choose Configure advanced user profile properties. You can also get there by going to Control Panel > System > Advanced tab > and click the Settings button under User Profiles. At this point, click on and delete all of the profiles that you wish to update to the new Default profile that you have created. Once all of the profiles are deleted, restart the PC and log on with these accounts again. The profiles will be created with the new Default template that you have created.
Now, the thing about this is that this only changes how the profile is created the first time an account is logged onto Windows. Once these new profiles are set up based on the template that you have built, they will not automatically follow any changes that you make with your master account. In other words, new accounts will be set up to look like your master account, but once the other accounts are created, changes made to the master profile will not affect any change on the sub-accounts.