Trade steering is used for two primary purposes. To move trade from areas where you have low power to areas where you are dominant, and to move trade from a node to the node where your capital is to avoid taking a trade power penalty. Trade being pushed downstream occurs wihtout a merchant in nodes other than your capital, but you cannot change which direction trade flows downstream unless you have a merchant there.
Here is an example of a game where trade steering is useful:
In this game I have roughly 50 percent power in both the Tunis and the Sevilla nodes, but my capital is in Sevilla. Because of this, the best course is to move trade downstream from Tunis, which sends 2.5 gold out of 5 to the Sevilla trade node. In Sevilla, I can capture 50 percent of that trade and get a total of 1.25 gold from the tunis node, times my actual income modifiers. On the other hand, if I tried to collect trade in tunis, i would take a 55 percent penalty to trade power, leaving me with only around 25 percent power. That would let me collect only .66 gold times Actual income. Trade steering is twice as good here. If I had no merchant at all, my power would push trade downstream, but aragon would make that travel to genoa instead of Seville. I would lose out on ALL income.
This is what the trade map looks like with no merchant:
I get absolutely nothing from the Tunis trade node, because I have no merchant there. This is caused by Aragon steering trade toward Genoa.
While it is possible to steer trade upstream, it is virtually useless to use a merchant to do so because the trade power penalty is severe. Steer trade downstream, not upstream.
Instead, you should relocate your capital to a the node that is furthest downstream which you dominate, and then direct trade there.
Should you always steer trade to your capital? NO!
Usually you will want to direct trade downstream, but not always. You don't direct trade through nodes where other players/AI have a lot more trade power than you, especially your enemies.
One good example of a situation where directing trade would be a bad idea occurred in my most recent game as Netherlands. I had a large number of colonies in the Chesapeake bay node. However, if I directed trade downstream, it would have been collected by England or Norway, in The North Sea and London nodes between Chesapeake Bay and Antwerpen. Instead, it was better to just collect trade.
Many people will tell you that you should extract trade only at your capital. This is FALSE. Here is an example of how much you can pull out of a non-capital trade node, without investing any ideas in trade. This is more than even in my capital.
The key to note is that I control 93.5 percent trade power, even with the large penalty to trade from collecting without a capital present:
This is because the trade penalty for collecting from a non-capital node is a trade power penalty, which means if you still have a higher percent power in a non-capital node than in your capital after the penalty, you should definitely collect there
The disasters are well documented in the EU4 wiki.
To take your peasants war as an example, here's how it should work:
Pre-requisites
- Is a monarchy (except Celestial Empire and Steppe Horde).
- Has greater than 5 provinces.
Progress
- Has no disaster ongoing.
- Manpower less than 25.0%.
Monthly Progress
0.5% when: not at war, overextension between 25% and 50%
1.0% when: not at war, overextension more than 50%
1.0% when: not at war, stability less than +1
1.0% when: not at war, war exhaustion more than 10.0
1.0% when: not at war, has taken more than 10 loans
1.5% when: not at war, legitimacy less than 50
2.0% when: not at war, nation is bankrupt
Effects
- +5.00 Unrest
- +50% Stability cost modifier
- Peasant's War random events.
Ends when
- No revolts are active.
- Stability at least +1.
So, the disaster should go away, if your manpower exceeds 25%. If it has already fired, you need to first defeat all revolts, and have a stability of +1.
Source: http://www.eu4wiki.com/Disasters
Best Answer
There is little else you can do. It is after all just a chance and a small one at that.
The simple act of making your ruler a general already significantly increases death chance(about twice as high). Battle do so as well. But the actual battle length isn't all that important. The longer a battle lasts, the more likely death becomes, in the end it evens out, as in the time a longer battle takes, you can do several suicide runs.
But even so, you are looking at chances of around 1%. Purposely killing a ruler or an heir simply is very difficult.
Also keep in mind, that a ruler/heir death in battle is a -1 stability hit, so if your ruler dies, you get -2 total (-1 from death in battle, -1 from ruler death)