25% privateers in a node - how?

[Cagallo]

There are some missions that require you to get to 25% of a node's trade power through pirating. What is the strategy for this? Is it something only really achievable at the mid-end game when you are big enough to get docks everywhere and build plenty of ships? Or it should be done early in the game before everybody gets plenty of development and modifiers?

I'm playing as Tunis and there is this mission saying that, if you get 25% of the node in Genova, then a pirate republic led by Barbarossa will spawn in Algers

 

[Stronghold]

If you've conquered tlemcen and morocco, then you'll probably have enough naval force limit to do this. You might need some docks to increase it.
Tunis has a national idea to increase privateer efficiency, which makes it easier

 

[iClipse]

If you have Golden century, you can do the easy thing and build a light flagship with only one modifier: + tradepower per ship in the fleet. Attach that to your trade fleet and privateer.

 

[Cagallo]

If you have Golden century, you can do the easy thing and build a light flagship with only one modifier: + tradepower per ship in the fleet. Attach that to your trade fleet and privateer.

Definitely

 

[RichardOlcese]

If you have Golden century, you can do the easy thing and build a light flagship with only one modifier: + tradepower per ship in the fleet. Attach that to your trade fleet and privateer.

There's a specific Flagship Modification that applies to privateering too. It's called Spare Jolly Roger. I have posted on the Suggestions subforum there should be a special Flagship Modification giving a better privateering advantage for Maghrebi nations.