What do you think of these espionage ideas?

[Fal]

Be subtle! Be Subtle! And use your spies for every kind of business. - Sun Tsu

I, for one, always enjoyed a good challenging MP game with graphs disabled, as one must rely on his spies, spells and diplomacy to learn the strength and weakness of his opponents. However, I have always thought espionage is largely overlooked in this great war game. IMO the espionage can, and should be improved in the next game, here is a list of spy activities I can think of and they should fit into the existing game quite nicely (along with some historical background in case you are not convinced ). I didn't want to post this in the Dom4 wishlist straight away as I'm hoping to get some opinions from you guys first, so please give your suggestions.

Spies have the option to sabotage opponent's construction activities, causing slight delay or minor loss of gold, for example spy activities forces you to spend say extra 20 gold when constructing a rampart, while an extremely skilled/lucky spy can delay the construction time for 1 turn and loss of 60 gold.
(Historically, the Norwegian heavy water sabotage initiated by SOE to prevent German nuclear energy project).

When sieging enemy castle, having a spy in the castle gives you extra siege points, causing the wall to breakdown faster. Naturally, the spy is unable to leave the province until the castle is taken by your force.
(Historically, the Mongolians employed extensive spy networks to spread propaganda prior sieging Chinese cities, as the Mongol horsemen earned their fearsome reputation from mass murder of Chinese civilians, the spy network was extremely efficiently in reducing morale of the defending armies which led to unconditional surrender of countless heavily fortified cities).

Planting spies improves your chances of intercepting/avoiding enemy army: e.g, army I located in province A wishes to attack army II located in province B, while army II wishes to attack neutral province C this turn. Assuming the sizes of both armies are equal and no terrain restrictions, by planting a spy in army II and giving him 'improve interception' order, army I's chance of catching army II in province B is slightly improved. Vice versa, if army II wishes to evade army I's attack, he should plant a spy in army I and give him 'evade interception' order.
(Throughout history military generals have employed scouts to observe enemy movement, planted spies to give false information to the enemy).

Spies can sabotage opponent's research activities, depends on his skill/luck, causing extra gold investment and/or loss of research points.
(Historically... well, there are numerous examples. The most obvious cold war aside, industrial espionage still largely active in technology-based industries such as biotech and computing).

Honeytrap: this works similar to succubus's seduction and will only work on opposite sex, and only over a period of time, say 3 months. The victim gradually attached to the spy who seduces him/her, eventually losing loyalty to his/her formal master and joins the cause of the seducer.
(Historically, US marine sergeant Clayton Lonetree sells classified documents to KGB after having affair with a female soviet officer).

So yes spies should be readily available to every nation in the game, but their ability of causing unrest should be limited. spies would have different leveling system compare to other military units (what's the point of having a lvl 5 spy anyway?). A higher lvl spy would be able to carry out tasks better than low lvl ones.

Just my 2 cents.