ER: system wide IP address aliases, or single page list of IP address variables

[rcfa]

I'm just considering how to set up a unit, test it, and then deploy it eventually.
One of the biggest stumbling blocks would seem to be to change all the IP addresses from the test environment to the ones used in deployment.
The feature set of pfSense is deep, and correspondingly, the settings pages seem near endless.
To adjust to changes in connectivity could be quite a mess, given the IP addresses used in Firewall, system configuration, VoIP, etc. and screw-ups seem to be virtually guaranteed.

If the aliases that now can be used for Firewall rules could be used everywhere where IP addresses can be used, it would make things much easier: everywhere things can be defined instead of by IP address or host name, by a name describing the function.
Then on a single page, all these names are listed, and the IP address(es) assigned to them. That would be a single go-to page to change deployment parameters.

Is that feasible?