Tech Trees

[Meneldil]

Hello, I'm currently trying to come up with original ideas for WTW Tech Trees, and a bit of help would be appreciated.

ATM, I'm aiming at doing a Skaven Tech/Building Tree.
What I'd like is to simulate the rivalry and internal struggles between different Clans. So, I had to idea to allow the Skaven faction to hire unit from only one clan per city (aswell as the common warrior clan units : slaves, clanrats and stormvermins). That way, the player would have to make a choice : does he want Clan Moulder's abominations, or rather Clan's Skryre's powerful weapons ?

I'm also facing another issue : should skaven get cities aswell as castles ? I'm not sure Skaven would make such a difference.

So, right now, the plan is something along those lines :

Tier 1 :
Slave pit - Tier 1 :
Skaven Slaves
Increase trade income

Altar of the Horned One :
Increase Public Order

Tier 2 :
Slave pit - Tier 2 :
Skaven Slaves
Further increase trade income

Warrior Clan Network - Tier 1 :
Clan Rats

Church of the Horned One :
Grey Seer (diplomat)
Increase Public Order

House of the Council :
Spy
Increase Public Order

Tier 3 :
Slave Pit : Tier 3
Skaven Slaves
Further increase trade income

Warrior Clan Network - Tier 2
Clan Rats

Eshin Training Ground - Tier 1
Night Runners
or
Moulder Experimental Pit - Tier 1
Giant Rats
or
Skryre Warplock Laboratory - Tier 1
Poison Wind Globadiers
or
Pestilens Church of Decay - Tier 1
Plague Monks

Temple of the Horned One :
Grey Seer (diplomat)
Increase Public Order

Embassy of the Thirteen :
Spy
Assassin
Increase Public Order

Tier 4 :
Slave Pit : Tier 4
Skaven Slaves
Further increase trade income

Warrior Clan Network - Tier 3
Clan Rats
Storm Vermins

Eshin Training Ground - Tier 2
Night Runners
Gutter Runners
or
Moulder Experimental Pit - Tier 2
Giant Rats
or
Skryre Warplock Laboratory - Tier 2
Poison Wind Globadiers
Warp Lightning Canon
or
Pestilens Church of Decay - Tier 2
Plague Monks

Tier 5 :
Slave Pit : Tier 5
Skaven Slaves
Further increase trade income

Warrior Clan Network - Tier 4
Clan Rats
Storm Vermins

Eshin Training Ground - Tier 3
Night Runners
Gutter Runners
or
Moulder Experimental Pit - Tier 3
Giant Rats
Rat Ogres
or
Skryre Warplock Laboratory - Tier 3
Poison Wind Globadiers
Warp Lightning Canon
Warplock Jezzails
or
Pestilens Church of Decay - Tier 3
Plague Monks

Great Temple of the Horned One :
Grey Seer (diplomat)
Increase Public Order