The combat will be taking turns getting to react to the opponent's attack and then unleashing your own attack. You cannot hit them in your post when you first unleash the attack, only say you are making the attempt to do so, then if the opponent does nothing to stop said attack in their next post, your next post you can have the damage be done in a realistic manner. 

Charging won't be that big of a deal due to magic not being able to get that powerful where it needs long charges. Well, I guess if it's a really well thought out power that would require a long charge then it may be allowed. 

I know it was controversial, but possibly being able to stop an opponent before they get their attack finished is a must. Therefore, if you have your character wind up a punch for a second and then having them spin around and slam his fist up into the opponent's chin, it's expected that the opponent can do something to stop him while he's still doing all of that, thus not allowing him to complete his move. It's not like you can always stop an attack; you must realistically be much faster then them to pull it off. So if some nimble guy just does a quick jab then I can't say I interrupt the jab with a powerful, wound up haymaker. If someone tries to abuse this in such a manner then the judge can say there was no interrupt and the attack did get through before it could realistically be interrupted.