Improve the definition of Constraint
Constraint is currently defined as “A constraint represents a factor that limits the realization of goals.” [6.3.5].
A constraint limits the way that a goal could be realised, and the idea is not just related to goals.
So it might be better to say this: “A constraint places, or implies, a limitation, or restriction, on the realisation of some aspect(s) of the form or function of the architecture”