I don't think it's been a taboo though has it, just the way things are because 'normal' shamans do all the spirit stuff and look after the clan health whilst the clan do everything else for the shamans. This means that their physical skills tend to atrophy to DEX x5 through lack of use and can only be improved through experience as they have no time for training. The same is true for Rune Priests actually according to the rules.
According to the vanilla rules only Rune Lords can get their skills up to over 100% and they always defend against spells at their full POW. But they do not have reusable Rune magic. T
I also don't see an imbalance particularly.
Then of course there are the Rune Lord-Priest who cannot improve in skills except through experience, but their gods prevent their combat skills them from dropping to DEX x5, and Rune Priest-Lords who can keep their priestly abilities.
From the basic rules the differences are:
Shaman | Rune Lord | Rune Priest |
---|
90% activity for clan | 90% activity for cult |
Stored POW | Skills over 100% | Reusable Rune Magic |
MAX POW for POW Gain = 25 | Defend at max POW | MAX POW for POW Gain = 25 |
Controlled Spirits | 95% chance Divine Intervention | |
Fetch | Allied Spirit |
---|
Spirit combat | Priest if POW >= 18 |
Way too restrictive for most and with cult write-ups the three generally merged over time. You could still say that the stored POW is a big advantage to shamans if they can also prey for divine magic. But when you take into account that they need to sacrifice permanent POW at a rate of 1 POW per 10 POW of the spirit they want to make a pact with then they'll not be sacrificing for many spells once they start trying to gather spirits.
Now compared with initiates then yes, I do see shamans as having an advantage, but only in the longer term, once/if the apprentices get to the point of having enough stored POW to start making pacts with spirits and by that time I should think the non-shamans would be getting towards Rune levels.