Very vague question here. Remote worker is a nebulous phrase. Using 96xx/96x1 versus AAfD, VDI Communicator versus Equinox client for Windows, Android, iOS and MAC all have various nuances and it all depends on which specific services you are going to need/use.
As kyle555 notes, newer is better. 7.2.2.1 is stable and not too many one-off configuration issues. Relay services, Utility Services versus Avaya Aura Device Services, CES for Visual Voicemail on iOS/Andoid, EWS, etc. are all going to play into this.
Certificate requirements are not very clear. Previous versions of Utility Services obtained their web certificate from RFA. Now you can obtain the certificate from System Manager or other CA. for reverse proxy services the nginx instance on the SBC will need to validate the certificate so Subject Alternate Names and DNS are critical items to address.