David, those are all good ideas, but I think they can lead to conflict, divisiveness, and a segmentation of users.
By establishing a "bullpen" where nearly no topic is restricted, people will eventually know who is of this persuasion or that and I believe it will inevitably spill over into the "non-partisan" areas. If people knew my true political/religious beliefs, I may end up with a zillion followers or be blackballed by the board. If you really want to know how I feel, read my comments in the Washington Post.
We have a huge, almost mind boggling, array of sites in the internet to express our views apart from rPods. Maybe we should follow the kiss rule and keep this limited to the things we share in common.
There is an additional reason for this. We have on our board people from all points of view imaginable. When we stick to talking just about rPod and camping related issues we discover that there are really a lot of truly wonderful people out there with whom we'd never interact if we knew their religious or political beliefs. Eventually, we get an idea of who is leans a little this way or that, but because we have to avoid hot button/dog whistle issues, we regularly interact with people who see the world much different from our own views and truly enjoy the conversation. If we saw how they really feel about certain issues, that would most certainly not be the case. [That is one reason one of my sons-in-law and I almost never speak.]
As for icons or emoji's to indicate one's willing to discuss issues, that's like wearing certain color clothing to communicate certain personal preferences. It will label people and lead to conflict. The PM system works just fine as it is. We can glean from people's posts or signatures already, enough information to know whether we may want to engage in a pm conversation. And in simply sending an email to someone you think may be interested in discussing how many angels can dance on the head of a pin and what happens to unbaptized babies when they die [I'm revealing my background], you can just ask. The worst that will happen is the person will tell you to buzz off.
So, I say leave it as it is. Don't fix it if it ain't broke.