You really should love The Cloud, if you don’t, well, stop reading. But, I need to use RADIUS with Wireless. And therein lies the rub! Once you try or move things to The Cloud this little part that is considered critical still exists. That little part is RADIUS. 

If you have some Windows Servers still in use, you could be fine. However, with Windows 10 and Azure Active Directory. Why even have on-site servers? Well, that RADIUS part still needs to be around. 

You can do a few different things, you can use JumpCloud that talks to O365/AAD and that works, but you have that little issue of delay for roaming. The other option is using NPS on a Windows Azure AD attached server and placing that in Azure(in The Cloud), or placing an on-site server running NPS attached to your O365/AAD site. That will reduce the delay, but you have on-site servers you need to maintain. 

So you mention the issue with delay, what are you talking about? Well, if you roam you need to authenticate. But you have key caching involved too? Wouldn’t that speed up the roaming? True, but I figure the goal is keep everything below 150 milliseconds round-trip. 

The goal is to be 100% Cloud based using services vs. servers. Why do you want to maintain servers?