Solution recommendation

With the end of support for Windows 7 rapidly approaching, you are going to want to move these users to Windows 10. As such, you are going to want to check the compatibility of their applications with the new operating system version, and where possible, try and standardize the applications as much as possible without affecting the user. Where there are applications that don't support the latest operating system, you could see whether VMware ThinApp would allow them to be virtualized and run on the new operating system. As the user has no offline requirements and they actually need to be online for the SaaS apps, this would seem like a good fit for VDI, and as there is a large commonality across the desktops, you should try and see how a non-persistent Linked Clone pool would work for these users.

You could deliver these common applications by installing them in the base image and then delivering the individual bespoke applications where possible using App Volumes. Additionally, you should look at Workspace ONE for delivering a unified workspace, from where they can access all apps and desktops from a single web-based portal.