Nice post. I think most of what you said here is accurate and I think I can fit my reply in the comment box this time lol.

I'm unsure if I'd agree with calling it a timelock token as Koin is actually removed from the total supply when burnt for VHP - it even influences the market cap. But yes it's hard to argue this and almost comes down to semantics. VHP is technically future Koin, but, only if someone produces blocks with it to turn it back into Koin. VHP does not have Mana though and you can't perform transactions with it. It's not the same as powered up Hive that does let you perform transactions while in this state.

Here is something I vehemently disagree with (respectfully).
Neither Hive nor Koinos have solved the custodial attack problem. Both Hive and Koinos can be thought of as proof-of-timelock tokens (which is why it's very easy to see that they both strong proof-of-stake elements as well). As long as a custodian is willing to timelock customer funds, they absolutely can influence on-chain governance.

I actually partially agree with you on this because it does operate under the assumption that exchanges will not destroy user funds and go insolvent. Ever since FTX, we know that this is a much more real possibility than it used to be, but, that means this issue is certainly not limited to Hive or Koinos either.

I will say this though: it would require a much longer time commitment of producing blocks for them to pull this off on Koinos. They'd also have to acquire OVER 51% of the entire supply in order to pull it off (or collude with other exchanges who also don't mind going insolvent to attack the network). Also remember it's 70% of all produced blocks for governance votes. It just seems really unlikely to me, especially if the marketcap grows higher.

Another interesting point is that since VHP does not have Mana like Koin it doesn't allow you to perform transactions, so, if they needed this to perform transactions for customers, they wouldn't have it. They also would need a ton of Koin to have enough Mana to actually produce blocks that turn their VHP back into Koin (or cast their governance votes by producing blocks).

After doing this research it's clear that the differences are so extreme that these two projects don't even exist on the same wavelength, which is a good thing. Diversity is important.

Yep - totally agree. I totally get that probably a lot of Hive user's would gloss over the fact that ex-Steemit employees were making a new chain. They'd probably assume that it was yet another Dan Larimer BitShares / Steem / Hive / EOS / Graphene clone, but, that's not at all what happened here and the intentions were quite different. It's just an entirely different animal.

Hive accounts as NFTs are the same thing.
We store them on chain, making them inefficient, but what do we gain? For starters, we gain the ability to have multiple keys associated with our account, modify those keys as we see fit, and even engage in account recovery when our account is stolen. Koinos can do none of these things because every public key has one private key and if it gets hacked you are fucked.

Hive accounts are sort of like NFTs yeah, totally. On Koinos this type of functionality would need to be implemented as a smart contract and be optional instead of required in order to still have plain old Bitcoin style addresses that anyone can use for free. A team is building KAP which has recovery features, "smart wallet" type stuff, and human readable names (both free ones for long names and paid for short). It's not the same, but, it gives the possibility to build an optional hierarchical key structure instead of a required one. They have their own whitepaper altogether (it's not being built by Koinos Group).