Block difficulty is constantly changing so the system approaches on 10 min block times.
No, it's not. Read & learn, don't just assume.
Read about the difficulty adjustment period. The difficulty is adjusted every 2016 blocks, i.e. about every 2 weeks. That hardly can be seen as "continuously".
"Best" can be quantified by basic quantifiable metrics like transaction speed, value spent, number of transactions, who spent transactions, where in the network they are spent from etc. just depends what the network is designed/optimized for
What does transaction speed means in your idea? Because the "speed" is related to the fee and the miners. So that's not a valid measure. Fee, maybe, but not speed.
Who spent the transaction? You should not know nor care who spent the transaction. Period.
Where are they? Are you kidding me? On a proper decentralized network this should never matter.
Number of transactions and so on are highly dependent on mempool, and, each node has a different mempool, so we cannot compare apples with oranges.
So.. all this "best" logic has shown (I will agree with franky1 here) that you don't know nor care about what bitcoin is and how it works, you just came with some half-baked ideas that cannot work.
Every 2 weeks does mean continuously though? Its a repeating process that is required for the network to operate properly?
When it comes to speed it cant be individually quantified but it can relatively quantified. The half-baked idea you are referring too I have already built and it works in local simulations so im not sure how half-baked it really is. Regarding who, bitcoin uses ECDSA signatures to sign transactions which means knowing who/public key is fairly essential in bitcoin. Where refers to where/how that transaction interfaced with the network.
If you dont understand how it can be done thats one thing but saying that these things are not possible is another. Rather than just saying im wrong it would be more productive for all parties to ask questions in order to understand what im trying to say. All im asking is that everyone try to come at this with an open mind because it is fundamentally a completely different approach to decentralized consensus. Let me clarify I'm not saying bitcoin is bad but rather asking the question is there potentially a better solution. Decentralized systems exists throughout nature and last I checked none of them use POW and have all lasted way longer than anything we have created.