"Are there other high value DPoS chains using 1t1v?"
I dunno. I only care about Steem.
While you're right in your next statement, that's about the kind of commitment we have been hearing from Roy Liu regarding powering down the exchanges and withdrawing Tron's puppet witnesses.
Do please differentiate yourself from Roy. I'd like your forthright consideration, not lawyerspeak.
Saying, "I don't know" but advocating for an untested change to be implemented doesn't work. 1t1v may actually be ideal, but until things are really thought through and tested, it could end up being a bad change and the witnesses would again be blamed for moving too quickly or going with changes that haven't been shown to be successful elsewhere.
Maybe EOS will go to 1t1v before Steem, and we'll learn a lot from them. I don't know.
You are the parties, you witnesses, we Steemers have elected to understand and effect necessary governance of the chain.
Please assess the facts and take a position based on your understanding - and not whatever some other chain I have no interest in or governance of does or doesn't do - so that Steem can proceed to deal with novel circumstances that aren't replicated elsewhere.
The math is simple. Make a decision and take a stand, which is what Steem needs from it's governance now. Failing to do this will result in delivery of the chain to it's extant majority stakeholder, as has been made clear. Even implementing 1t1v is not proposed to prevent that stake advantage. All it does make possible is accurately weighting the stake of voters per their holdings. Sun's stake is magnified 30x by 1t30v, and that's the present circumstance.