"Do more" - do what exactly? As you said above, bitcointalk got compromised because "bitcointalk lost control of its domain name, which is its identity
Yes, and that's the tradeoff you make when you make your domain name your identity.
If BitcoinTalk was a real organisation or company, it could have got an EV cert and that would have been much harder for an attacker to duplicate. But it isn't. It's just a website. You get what you pay for.
You having gotten an EV cert doesn't protect you against some other CA issuing a non-EV cert and someone using that cert for malicious purposes. Again, we're talking about your proposal of "mini-roots" of trust, and I've shown quite clearly why it leaves users more vulnerable, not less.
Of course, if you were to be getting involved in a business trying to sell end-users certs that'd be another matter... What's Circle doing in this space anyway?
Even just my proposed compromise with "pseudo-CA"'s based on multiple trusted/semi-trusted roots of trust is a serious competitor
I'm all for exploring new ideas, but reality check time: your proposed system doesn't exist
Neither does yours, and all prior attempts to make it exist have gone nowhere.
and all prior attempts to make such ideas not suck have failed. PGP has been such a colossal failure that even people who should have been highly motivated to use it refused to do so; people like terrorists and investigative journalists whose lives were on the line.
In contrast the CA system has verified tens of millions of identities and is in use by over a billion people. You cannot make a bunch of forum posts and claim to have created a serious competitor to it, sorry.
What you really mean is that person-to-person crypto is a colossal failure among average people. The CA system gets used semi-effectively for websites, but for identifying people, hardly at all. OpenPGP doesn't get used for websites, but among security conscious parts of the tech community it gets used, and as I showed above in my Tor example it's effective among that knowledgeable crowd.
It's really telling that in your example of terrorists and investigative journalists someone in either space saying "Hey! Here, use this S/MIME key with me to communicate!" would actually either get the response of either "Huh?" or if they're a bit more knowledgable "Um... why isn't he asking me to use that secure PGP thing? Am I being entrapped by a government agent?" And heck, for terrorists specifically, using electronics communications at all would get that response... you might want to ask yourself how the security, or lack thereof, of in-browser-cert-stores is going to play out among real end-users with compromised machines. There's a lot to be said for the much simpler Trust On First Use principle Adam Back has been pushing lately. Part of the idea behind stealth addresses is to make TOFU-style usage easier without sacrificing privacy if ever you want to have your using peers cross-verify the addresses.