Personally I think that having "dungeon" style combat for things like assassinations, special missions inside cities (say you are sending some champions to whack a crime lord who is siphoning off money and threatining control of your city, at least the underworld portion of it) and special missions against other factions and sovereigns (because you just have to have that artifact) is a must... if not for elemental, then for an expansion.

While I'm hoping for excellent mechanics regarding stealth encounters, this feels contrived.  An honor guard is entirely logical, you'd be hard pressed to find the leader of a nation that doesn't have one.  Why put arbitrary limits on it though?  Just use the same unit design system everything else will be running off.  If you can attach champions to regiments, permanently or temporarily, you've got the perfect setup already.  Just join them up with a group, or retrain them into one, however it's set up, and call it a day.

Same deal with assassins, there shouldn't be any such unit at all, just methods of making every day units sneaky bastards.  However big a group you can sneak up on the army with is as big a group as you can get in.  Assassination can be a combat option when you, the sneaky bastard that you are, successfully sneak up on an unsuspecting army.  Lets say they get a special tactical battle.  The enemy units are inactive, with lookouts on a set patrol path perhaps, until you alert them, you're the only side active.  If you get to your target without anyone noticing, you've got time to ream him out while the surrounding army goes for their weapons.  Trying to assassinate someone in an army with sufficient recon would be suicide.  Assassinating someone outside of an army would just be a matter of getting to them and being the bigger badass.

Why would you only want to assassinate envoys?  Why would the Sovereign be an envoy?

Assuming you only want to assassinate envoys, at least put the word "envoy" somewhere in your highly misleading post.  I'm a psycho, not a psychic.

I'd still much prefer just adding the hero unit into a regiment.  More important people is terribly subjective.  If I can do it, and I want to guard an envoy with a thousand people, let me make the stupid choice?

I like the idea tasunke, though it seems overly complicated to me. i remember seeing a post once about being able to create an "order" or such. i think the idea (or maybe im projecting here) was to be able to create an order which would give various bonuses to what ever unit is a part of the order/group.

so say i made a order dedicated to protecting the sov, or family. ill call them the royal guard cause im kinda uninspired right now. they would gain bonuses like +def when in battle alongside their fellow royal guards. and an even better def bonus and possibly a higher rate of attack while a sov or heir is present.

as far as who can join. you could limit it to champions or decide to open it up to regular units, maybe both. balance it by limiting bonuses on huge orders. and to stop everyone from always making every unit in their army part of an all powerfull order of knights or something. make them cost three times as much to produce and maintain.

i know this isnt the best idea, but i feel if made better. a system like this would satisfy tasunkes want for smaller either elite or champion based hit squads or personal body guards. while still allowing for larger elite armies if you wanted. for some reason this appeals to me. im a dune freak! and since i heard about this game some time ago, ive been imagining dominating the globe with iconic ripoffs like the brutal imperial sardaukar, or later emperor leto's all female fish speakers. and hey the whole breeding aspect just begs a bene gesserit like faction! enough dune geekery for now, i know ive gone on a tangent. imagine creating a special sub group among your heroes and units, being able to give them a cool name and having it actually count for something! im just tying to express how having a more generic "order" template, which can be adjusted one way or another, can only add to the strategy and customization of the game.