Numbeo is great, I used it a lot when I was planning my move from UK to Taiwan many years ago.
Hive has an equally, if not more diverse user base, and we could potentially create a much more meaningful index, imagine Hive having the first and biggest blockchain PPP index. Your last point for onboarding is brilliant, I hadn't even thought of that!
I'm just using excel this time round and it's fine up to a certain scale. Let's see where the community goes with this