From what I see in aikido classes, the strikes are for setting up/distracting the other person. They would be usless to stop a real attacker. Don't fool yourselves.
The other stuff can work, but, please, don't try to punch an attacker - you're wasting your time!
Plenty of strikes to set up/distract the other person in boxing. I don't know, maybe they're fooling themselves... :-).
Plenty in sumo, too, although they're restricted to using an open hand (doesn't stop them from generating a great deal of power, though).
Daito-ryu, for that matter, uses strikes at times in order to set up portions of techniques, so the practice goes back to the roots of Aikido.