Thought I'd make a list of countries that are good to vassal feed, mostly depending on them taking religious ideas (if you want them to convert stuff for you) or NOT taking aristocratic ideas (to avoid the increased costs). The order of ideas taken isn't set in stone, but is roughly correct.
Takes religious as first idea-
Asia:
Ainu
Garjat
Hedjaz
Iraq
Kara Del
Kashmir
Najd
Nepal
Nogai
Orissa
Perm
Sarig Yogir
Shammar
Tibet
U-Tsang
Vijayanagar
Yarkand
Africa:
Ajuuraan
Mzab (great for North Africa converters)
Warsangali
Europe:
Albania
Bremen
Cologne
Corfu
Crete
Epirus
Frankfurt
Galicia
Livonian Order
Luneberg
Magdeburg
Mainz
Mantua
Montenegro
Munster (HRE)
Naxos
Teutonic Order
The Knights
These countries take aristocracy first (kill ASAP)
Baglana
Hadoti
Nagaur
Norway
Marwar
Mewar
These countries take aristocracy second
All Irish minors, and Ireland
Cornwall
Northumberland
Wales
Rewa Kentha
Jaisalmer
Jangladesh
These countires take aristocracy third
Denmark
Have other core creation maluses:
The Caucuses (all of them)
The Berbers (all of them, including Mzab)
Dai Viet
Wallachia
Central India and Rajput nations
Brittany
Holstein
Bohemia
Moldavia
Afghanistan
Takes religious as first idea-
Asia:
Ainu
Garjat
Hedjaz
Iraq
Kara Del
Kashmir
Najd
Nepal
Nogai
Orissa
Perm
Sarig Yogir
Shammar
Tibet
U-Tsang
Vijayanagar
Yarkand
Africa:
Ajuuraan
Mzab (great for North Africa converters)
Warsangali
Europe:
Albania
Bremen
Cologne
Corfu
Crete
Epirus
Frankfurt
Galicia
Livonian Order
Luneberg
Magdeburg
Mainz
Mantua
Montenegro
Munster (HRE)
Naxos
Teutonic Order
The Knights
These countries take aristocracy first (kill ASAP)
Baglana
Hadoti
Nagaur
Norway
Marwar
Mewar
These countries take aristocracy second
All Irish minors, and Ireland
Cornwall
Northumberland
Wales
Rewa Kentha
Jaisalmer
Jangladesh
These countires take aristocracy third
Denmark
Have other core creation maluses:
The Caucuses (all of them)
The Berbers (all of them, including Mzab)
Dai Viet
Wallachia
Central India and Rajput nations
Brittany
Holstein
Bohemia
Moldavia
Afghanistan
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