I would highly recommend using Visual Studio Code and installing “The F5 Extension”. It has a feature called “Config Explorer” which will allow you to import your UCS file and browse all the configuration files on the BIG-IP very easily:
The F5 Extension on Visual Studio Code - Config Explorer
The UCS file is essentially just an archive. So alternatively, you could also just open it up with software such as 7zip / Winrar and then browse through the directories to the bigip configuration files.
If I deployed a VE to a test environment (without active network connections), could we load/restore the .ucs backup so that we could view settings in the UI (preferable) or CLI? Is there a better way to view previous settings/configs? If this is possible, do we need to deploy the VE as the same exact firmware version?
Yes, you would need to deploy the VE with the exact same firmware version that the UCS was originally saved in (15.1.x), otherwise it will fail to load.
You should also copy the F5 master key from the old device to the new VM otherwise the UCS may fail to load due to decryption errors (should you have any encrypted passwords / passphrases in the old device’s configuration)
More details about the F5 master key here
On the new VM, you would load the UCS from the original device using the following command:
tmsh load sys ucs <PATH TO UCS FILE> no-license platform-migrate
So in summary, if you absolutely need to view the configuration via the UI (BIG-IP Configuration Utility), then loading the UCS file from TMSH using the command above would be your best bet. But, you need to be mindful that you may need to copy the F5 master key from the old device to the new VM to avoid decryption errors when loading the UCS. You also need to make sure that the F5 BIG-IP software version matches on the new VM.
If you are comfortable viewing the plain text configuration files, then Visual Studio Code with the F5 Extension is the way to go (it would be my preferred option).