BI: why do the shrines suck?

playing as the saxons the other day, it occured to me how crappy many of the temples of this faction are. The woten shrine settlements are usually red faced due to the awsome 5% bonus to happyness Donar gets almost as bad 10% with shrine number 3 being the only one which cuts the slack at 15%. Granted all these come with a military bonus' but that's funk all use to me when it trying to keep my towns in the blue/green. At the same time it occurs to me that the damn priests are gone! Running through the various factions shrines and observations from previous games here's what I've found:

Pagan shrines
-poor happyness bonus'
-no fith teer temples (even for the Romans who've magicly forgotten how to build pantheons)
-The Roman priests are rubbish compared to their predessesors (compare a priest of mithras to a priest of saturn to see my point) plus pagan priests don't get a conversion bonus.
-none of the pagan barbarian temples have priests anymore
-the barbarian temples only go up to three....which was fine when they only had three teers but kinda makes it tricky when they've got five.
-I'm not sure about this one but no relics

Christianity
-More religious personality defects than Pat robertson, fred phelps and Thomas de tormequada combined
-their temples are tiny on the battle screen (I know I'm being pedantic)
-why have Aryan Christian got Aryan heretic flaw...surely it would be a good thing for them?

Zorostrianism
-one damn faction!!!!!
-I'm not sure about this one but no relics

Considering how much of a boon temples where in the origional why do you think temples have been so weakened in barbarian invasion? my best guess it to imply the total and utter entropy of the late empire but that doesnt explain the pagan shrines weakness.