I definitely agree in that uke is not passive but should be an integral part of the technique. If uke responds in one way, the techniques proceeds as such, if uke respends differently, the techniques proceeds differently. I think that both uke and nage need to be aware of this and work hard to not get into the "dance mode" of doing techniques.
Sometimes, as nage, I will choose to not respond when uke attacks to see if they are attacking correctly or if they are just gonna give me the technique. Especially with kohei, this can make for a nice "teachable moment" to talk about proper ukemi and making a good attack, etc.