Perhaps as Alan pointed out in another thread we should also look to the usefulness of the bonus actions. Perhaps to modify cost for those classes as AA, or to level out the the bonus in some other way?
Yep, I like that idea too.
I think having a second option for a bonus action is a clear advantage in flexibility (I found it very useful in RoE2 anyway!).
In addition, perhaps some consideration or weighting should be given to the type of action granted (some actions are more likely than others to be used every turn)?
Also, having a second full regency domain is (IMHO) a clear advantage compared to 1 Full and two half's... in this case, I do not think that 2 half's do not add up to the value of a whole.
Finally, the "right" combination of multi-classing to max out domain and bonus class actions offers stinky cheese, er, I mean an "advantage" in this area as well.
Perhaps some sort of "cap" might be a solution?
Good discussion!