Advice on eliminating on-prem IT resources

Just asking for some advice from SDMB members who have Windows Server, network, and VOIP experience for the best way to handle a downsizing project that I’ve been wrestling with.

A little background first: This is for a family-owned company where I worked for 26 years in the IT department. In 2021 they sold off their retail units and reduced their corporate staff from fifteen people down to five. I was not one of the lucky survivors, but I agreed to help them with IT-related tasks on an as-needed basis. It should be noted that of the five people still employed there, none of them work full-time and none are working remotely.

Fast forward about 18 months later, I’m still doing the occasional odd jobs for the company. The task before me now is to retire the Windows servers that are on-premises since they’re overkill for the current needs of the company. In addition I am going to replace the old PBX phone system with a VOIP solution and replace the obsolete Cisco ASA that’s currently safeguarding our network from the outside world. I’ve already had to do some repairs of failing equipment, so I’m aware that this is a ticking time bomb I’m sitting on.

I’ve reached out to a local IT support company to help me to break free from my old company and give them a much simpler IT environment that can meet their needs with minimal or no involvement from me. I’ve already begun the process of archiving and deleting seldom-used files and folders from our servers to reduce the amount of data that will be moved to the cloud. The company currently has their email hosted using Office 365 Exchange services and Azure Active Directory to sync up with our domain accounts.

My thinking is that I can probably get most of the way to my goal by simply converting our existing hybrid Exchange accounts and Office 2013 Standard users over to Microsoft 365 Business Standard or Premium and move the remaining files from our servers over to SharePoint libraries and OneNote folders. I would then shut down AD synchronization and take down our Windows servers and have the users set up on local accounts on their Windows PC and laptops. I would then look for a cloud backup solution to protect everything that has been moved to Microsoft 365.

Our local phone company offers VOIP services and support, so I would farm that out to them, and local hardware and network support would be done through the IT support company mentioned above. I know that I’ve hand waved a lot of details, but I just wanted to give a broad view of how I see things happening.

I’ve been tempted to just move the remaining user and shared data from the servers onto a NAS that’s on the company LAN and use Veeam NAS Backup to perform regular offsite backups to the cloud, but that almost seems too simplistic and prone to eventual failure. Am I wrong about this, or is this maybe the right way to go? I agonize over this a lot lately. My wife says that I shouldn’t since the company did end my employment there, albeit with 6-month’s severance pay.

Just looking for some outside opinions or suggestions about what you would do. Thanks in advance for any tips or suggestions.