All great advice, thanks, guys.
I think my cats may have sorted their differences out. I have decided that the majority of the time they spend "fighting" it's really just them playing. That's how kittens play. I had never really been in a household with cats that got along so this was hard for me to interpret. But, it IS sometimes hard to tell if Chimmi is being malicious toward Magic, so, despite the "rules", I break up the "fights" if it gets too rough. It seems that Chimmi is really aggresive but not really in a mean way, she just gets carried away, I think.
Magic has begun hiding from Chimmi, though, after these episodes of rough play and I'm not sure if this is a game with kittens or if he's scared for dear life but he seems really calm whenever they have little breaks between rounds of wrestling.
I think that once this initial period is over, they'll be buddies. I guess it's just a matter of time now. There's not really much advice that can be given on this matter, actually (now that I think of it). It all sorta depends on the cats.