The only way you'll get what you want is to hire a secretary to pre-read your email... and even the warm body will make mistakes.
Also, end-users don't install spamassassin etc, it's done on the inbound email relays through which everyone's email is received... and running mail relays is a non-trivial job.
Why should I have to go through that expense and loss of privacy>
Boy, I have to say I am disappointed with my fellow freepers.
So many reasons why suggestions won't work, and why nothing can be done. But not to many positive suggestions.
The whole idea of brainstorming is that one suspens the critical function untill the process is over. The idea is to get as many ideas as possible on the table.
Then once they're all out there where everyone can look at them, that is the time to beging analyzing them critically.