I have very mixed feelings about this thread.
On the one hand, most 'creative spellcasting' involves the player telling the DM what the results of his action are. This is a player stance that I find very annoying, particularly when it involves going outside of the rules. I don't mind telling me what you intend to do, but don't decide for me whether its going to work. It's my job to decide that, and I don't want to hear, "Well, if I knew that was going to happen, I wouldn't have done it. Can we have a do over?", in terms that are usually more beligerant than that. Moreover, most of the time the player playing 'creatively' wants something for nothing. What they are really asking for is a lower level spell to emulate the effects of a much higher level spell.
On the other hand, one of my rules of thumb as a DM is 'Don't say 'No'.' I don't like to give the player nothing, especially when they are doing what they are supposed to be doing which is think inside the box. (No, really, imagining creative uses for a spell is inside the box, where the box is our little shared imaginary universe. Thinking outside the box would be thinking that because the rules say what a spell does, it can't ever do anything else.)
Give a simple example. Suppose a player wants to cast 'light' at someone's eyes. (In earlier editions, incidently, this was perfectly legal.) To me, in theory this seems like a perfectly reasonable thing. If you can make light shine in space, and with some sort of range, and you can choose the location, why not? The problem comes when the player wants to, "Cast light at the anti-paladin's eyes to blind him.", and then insists that he ought to be able to do that because, "it's creative", and starts to bargin with me about it. What he wants is to use a 0th level spell to do something that you'd need a 2nd or higher level spell to do. The spell he's using is more limited than that, and frankly, making up some effect isn't creative. Using what you have is creative. Looking at light, it's got a range of touch, so you'd have to make a touch attack, and its got a target of object, so target a helm or a visor not 'eyes'. And looking at other 0th level spells, permenent blindness is out of the question. Being dazzled for a short term is much more reasonable. And obviously, sence this is an attack, a saving throw would be granted.
As for 4E, it's hard to imagine that the rules would kill creativity since by definition, we are talking about going outside of the rules. What might serve to kill creativity if anything is spellcasters having a reduced selection of spells (both per day and on their allowed spell lists) with the ambiguos spells removed in favor of simplier cleaner 'blast' type spells. I really wonder how a pure illusionist will play out under the suggested rules. I can imagine a 'ray of cold +6'. I have harder time imagining a 'simple illusion +6'. But we will see when we actually see the mechanics.
Once again, speaking as a programmer, I can't help but think that the driving force here is to make everything easily implementable on a computer. 'Creativity' really means 'needs a DM's input', and you can't program that into a computer.
, has anyone considered just how awesome unlimited warlock-style power-blasting (which seems to be the closest comparison to the at-will combat spells in 4e) would be if D&D attempted more to simulate actual reality? Take a fighter and a wizard who have been captured by bad guys and stripped of their weapons and armor... and all of a sudden the wizard can start freely blasting people with his bare hands, once per round, nonstop??!? :/ Madness! It's only because D&D is so heavily tactical and has so little of a simulation-of-reality "HOLY CRAP! THAT GUY SHOT FIRE FROM HIS HANDS!" element that this doesn't seem as awesome as it is.
