I consider "core" everything that is run by full node operators. Right now to run a "full" node the operators have to provide:

• hived
• haf + hivemind
• jussi (or something capable of providing the same functionalities)

We created a simple HAF a few months ago. We have not been able to get any node operators to run it 😔

But I totally agree with you that this is something to integrate directly into Hivemind. As far I've seen it would require at least one additional DB index. Do you think it can be added in one of the next updates?