In the heat of the moment, I think whatever action it took you to keep you and your roo as safe as possible was the correct one.
My feeling is: Get away safe from whatever situation first, figure out a strategy later. I guess I read your post a bit different than others, I did not see that you were going after some helpless rooster, who was minding his own business. I read that you were ATTACKED and were defending yourself in whatever manner you could. It wasn't like you could say, "Hold on there a minute, <insert roo name here.>. Let's talk this out." Doesn't sound like there was time.
I haven't kicked my roo, but if he was attacking me I wouldn't hesitate. And I HAVE chased him around before for lesser crimes (I do not feel he should be crowing in my presence.. since lower ranking roos do not do that to superiors.). So far so good with my guy. If I pick up his hens, he keeps an eye on the situation, but doesn't interfere. We respect him, also, though, so my kids aren't allowed to chase or scare the chickens. We don't brutalize anyone. All are loved, and respected.
Heck, I'm a HUGE dog lover, but if some nasty beast was trying to bite me, I'd kick, hit, punch whatever it took to keep myself safe. I wouldn't consider THAT abuse. Now, if you casually walked into the run, your roo was eating, and you proceeded to kick him all over the place.. now THAT would be abuse.
Stay safe.. then come up with a strategy. and sounds like that is what you are doing.
Good luck with your roo. Hopefully he learned his lesson, and won't try it on you again.
Meghan