I feel like most of what I do day-to-day is finding the best way to collect inventory information from our Mac fleet. I try my best to track our serial numbers for purchased software as best as possible, but our org is a bit too small to afford volume licensing for everything we use so one-offs sometimes get lost in the shuffle, especially when a request goes directly to our purchasing folks and not through the Help Desk team (purchasing always purchases, but without additional communication sometimes keys are handed off and we don't know they exist to track at all). Spreadsheets are only as useful as the people who updated them, as the saying goes.
For a while we were using this EA from JAMF Nation for OmniGraffle 5, but found it stopped working. It was also totally irrelevant to OmniGraffle 6, which has all of their app data sandboxed. After booting up a VM and doing some test installs, as well as some help from the #jamfnation channel the MacAdmins Slack, I've got EAs created for both apps. I'm listing them here separately, but I'm pretty sure you could combine both into one EA if you wanted to do so.