So I don't know what the game's data infrastructure and set up looks like so there may be limits on what's actually feasible but here are my thoughts on potential ways to improve the issues I've identified:
1) & 2) Fixing realm stagnation and elites hoarding power is always going to be impossible to fix through mechanics but I do think some better guidance for rulers/dukes would be a good thing.
E.g. the ruler options could say something like "you are STRONGLY RECOMMENDED to share most information (though not all of it) with the realm as a whole and to encourage discussion even if you intend to ignore your subjects' opinion" and anything else that reminds rulers to take a key role in encouraging activity.
Equally, it might be useful if, in addition to the protest mechanic, there could be a way for knights to be discontented in a similar fashion to the way peasants can be discontented. There could be an option under Politics to set your room about the realm's direction to Happy, Content, Discontent, Unhappy, Neutral and then a weekly report could be sent to the realm with a summary of the mood of the realm's knights and lords according to category. That way characters would know what the overall mood of the realm was and have an anonymous way of giving feedback on the realm without having to stick their neck out with a public letter or protest. It would also give characters a way of knowing if the public mood might be safer for actual protest, public letters criticising the government or even rebellion - so it could be something which could enhance the use of the existing mechanics rather than taking away from them.
I also think that, in addition to improving the detail and guidance in the character creation process, when it comes to choosing a realm the Activity metric should be massively promoted and flagged for the player's attention. This would reward realms that are active and penalise realms which are inactive, which is a good thing. Because it means an active realm would gain nobles faster and therefore be more likely to beat realms with low activity which would in turn help encourage realm destruction and creation with the inactive realms gradually being eliminated in favour of those with a culture of activity.
It would also be great if there could be an alert displayed in game to everyone in a realm on a regular basis if their realm didn't have a description written for the new character creation process and if there was a reminder every two months of what the realm's description currently is just so that it doesn't just get forgotten or neglected.
3) Improving guidance within the game could probably just be a matter of improving the splash page for when you've just joined a realm to contain more advice and maybe including a brief description of each of the Actions, Orders, Politics, etc. tabs to say what they're for - ideally as hideable hints for new players that get auto-hidden after a certain amount of time in game.
4) There's only so much that could be done to improve the knight game but I think that one good mechanic would be either to open up the guild creation/construction mechanic to any noble with an estate (although only with the permission of the region lord) or to give knights the option to create mini message groups to expand the potential for knights to interact with each other from a social and organisational perspective.
Also, anything that would give knights the option to do more with their estate and/or unit would be a good thing. If I'm playing the game as a knight and I know that if I can save up enough then I'll be able to, for instance, build a smith at my estate so that my men (and my men only) can repair a limited amount of equipment damage, or build a new farm that will increase my tax income by 10%, or even just build a new manorhouse with a description that will be seen by anyone who looks at the region page, then it would give me achievable goals to work towards and deepen my connection to my estate/region in a way that just doesn't exist at the moment.
Equally, being able to create a character description in game (see point 5) which my character's name would link to (e.g. if a message comes from Sir Kepler then everyone who receives it can click on Sir Kepler's name and get taken to his character stats and description) would help improve my investment in developing my character from an RP perspective.
5) This leads neatly on to ways to improve the opportunity for player created flavour in the game. Obviously this would have an impact on the database and storage space could be an issue but here are a few things that I think could work well:
Newspapers
The Politics tab could have options to start a newspaper and read the newspapers. Anyone with enough gold could start a newspaper and any newspapers created on a continent could be read by any character on the same continent.
Newspapers could basically consist of one or more editors who could write and publish articles which could then be viewed on the newspaper's page in game. Articles would basically just be letters but without a sender name (it would be up to the author to include their name or pseudonym within the article). There could also be a button to allow any character to write to the editors of a newspaper to allow them to submit an article or share news which the editors could then publish.
Alternatively, a character could subscribe to a newspaper and articles from that newspaper would show up in the messages feed as they're published.
I don't think there should be any efforts to set up official newspapers for a continent or concerns about bias and propaganda. That should be left to players and a blatant propaganda sheet by one character could just serve to entertain others and maybe prompt them to start a propaganda sheet of their own.
Realm History and other flavour
Database storage could be an issue here. If it is then the only workaround I can think of is creating a way to view and edit (editing only for certain characters and if necessary through a shared wiki account) wiki pages in game. So a Realm History link on the Information menu could take you to an in game view of the appropriate page on the wiki - the key thing is that players should at least be able to read flavour content without leaving the game.
In terms of flavour content, there's already the option to build monuments with descriptions and create/edit ruler/judge/banker/general bulletins, etc. So creating, editing and viewing descriptions in game is already possible with current mechanics.
What I think is that there should be more places to put descriptions. You should be able to create an in game description of your character's appearance with other characters can view. You should be able to create and update a Realm History in the information pages (which even characters in other realms could read). You should have a way to view a game generated list of a realm's rulers (even if historic data can't be recovered it would be nice to have going forward). You should be able to write and view a description for an army (which would give you a way to record medals and other honours for heroes). And you should have space to write a more detailed realm description so there's space to talk about the realm's culture/alliances/etc. rather than being limited to a very short bulletin.
If it's not possible to store this information on the database then hopefully it would be possible to store it on the wiki but make it accessible in game. What I definitely think though is that you shouldn't need to leave the game just to be able to access the most basic lore, flavour and history about your realm at the very least. And if it is stored in game then there should be a way in which it gets copied to the wiki.
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Which reminds me, does the wiki have any kind of API?
