In my proposal, the difficulty keeps halving every 20 minutes without blocks. So it wouldn't take that long.
How do you propose on doing this in a decentralised ecosystem where there is no centralization "clock" that keeps records of the events
The same as the current system: nodes keep their own time and reject blocks that don't fit in.
anything you build on needs to be a proved by work, it needs to be a part of the blockchain, otherwise I can just run dozen nodes and set time in the future and claim all of them took 20 mins to mine.
I think you can do that in the current testnet already, but other nodes will reject your blocks and create their own chain.
for a 1k max block you are going to need to adjust the rules of difficulty adjustments, maybe 2 blocks, I am just throwing random numbers here, but I suppose the concept is clear.
I think that can indeed work: 1000 blocks in 10,000 minutes. That's almost a week, then reset.