IPv6 is here to stay. Removing it can break networking. Do not remove it.
SMBv1is a security hole and has been removed from Windows 7 & above, Server 2008 & up.
SMBv1 has been removed meaning you cannot connect to old operating system, old NAS devices and old printer/scanners.
SMBv1 is a security hole. Do not enable it.
Window 10 is going to update. Get used to it. The people who turned Windows 7 updates off and then blamed Microsoft when their operating got hacked and hosed caused this.
Home group has gone (Windows 10 V1803 and up). Get used to Password Protected sharing and learn how to use it. I wrote an article about this (look in my Articles for Folder Sharing on modern computers). Do not turn passwords off.
Windows 10 is not Windows 7, does not work like Windows 7 and has dispensed with some old Windows 7 ideas. There is no going back. Get used to it.
You got ransomware from people opening email from strangers. Get a Spam Filter. Train Employees, keep Off-Site backups. It is not a technology problem - it is a management problem.
Amortize expensive software and hardware to create cash for new equipment. "I am stuck on XP because the equipment is too expensive to upgrade" is not an option. Get your accountant to explain this to you.