Most of your points are about increasing communication. A lot of this can be achieved through frontends -- a custom field to fill out when upvoting and downvoting which would be recorded along with the vote as part of custom json. It's possible. The trails could also be managed in the same sort of way but all they'd say is 'trail vote' or along those lines (where the trail is controlled through a service and not a personal bot). One issue is that voting would be more 'expensive' simply because instead of one, two transactions would need to be sent. This wouldn't affect most people however.
In regards to the same witnesses being there it's largely to do with the fact that witnesses have to work together, understand the protocol code, and it's generally not inexpensive in relation to resources. Around hardforks, for example, I have at least 4-5 nodes on different servers running. Every hardfork we end up seeing the same people engaged from both the consensus and backup witnesses. In the pre-Hive days, access to witness communication resources wasn't accessible to all, it was tiered. Now it's all easy access from various platforms to the same chat. Hive completely changed all of that.
I agree in regards to the power down/unstaking, it would be a good idea to start projections of what lowering it could look like.