Imagine having this debate in a karate forum: "Should punches be strong?". kinda funny isn't it?
Should punches be strong in aikido? Not necessary. But our blending better be. Blending is the essence of aikido (in my opinion).
Punching and blocking like it is found in karate is about stopping force not blending with it.
So the better question would be, "Should karateka blend more and punch less?" Why do you punch so much when you can blend? Because that is not what karate is about, perhaps?