Although Nevercast is not a fantasy rpg, the mechanics could easily translate into a fantasy setting. Here are some ideas.
Magic
The use of metaphysical energies will require the wizard to possess a broad spectrum of abilities. Focus controls the intensity of your expressions and how much metaphysical energy you can control before you start to tax your ability to concentrate. Awareness dictates how much complexity you are able to add to your expressions. (Techniques that allow the wizard to apply complex conditions will provide for a fluid system of magic.) Since your ability to concentrate is finite, you must make the decision to have more complexity at the cost of intensity, or vice versa, or a balanced level of both. Having high levels of intensity and complexity is likely to tax your mind and/or your body quite heavily.
There are two general uses of magic: to manipulate internal energies and to manipulate your environment. Manipulating internal energies is very physically draining, and using magic above your comfortable thresholds will result in fatigue, inability to concentrate, and sometimes nausea or bodily harm. For example, conjuring a fireball that is too powerful will cause burns on your body.
In contrast, manipulating the environment is far less demanding of you, but the environment you are in limits what you can actually do. You will not be able to conjure a rock monster on your boat, and it will be more difficult to conjure a lightning storm on a perfect day. In both disciplines, you will require extended recovery time if you surpass your thresholds.
If you are engaged in melee combat with an opponent or if conditions are very chaotic, it will be very difficult for you to use spells. Thus, it would benefit the wizard to take actions that buy him the time, shielding or distance to use magic. Or, if he is competent at armed combat, he may enhance his fighting abilities ahead of time and jump into the fray (I always wondered why Gandalf bothered with swordplay).
There are two ways to improve your magical abilities. One is by learning techniques which allow you to manipulate the spells in various ways. The other is to learn spells. In order to learn internal spells, you need a high enough Insight attribute in relation to the spell's power. In order to learn environmental spells, you need a high enough Logic attribute in relation to the spell's power. Although techniques can be learned through experience, spells are typically learned through a teacher or some text which describes the proper movements and visualizations necessary to cast the spell (higher attribute requirements if learning spells through text).
Slaying Dragons
I simply cannot wrap my mind around how a medium-sized adventurer in D&D is able to endure 30 foot wide cones of fire, umpteenth-level spells, or a 14 ton tail swinging at them and then run up next to a colossal great wyrm and hack at its sequoia-thick ankles until it dies. And I don't care how magical your +5 sword is; a 37 inch blade can only sink so far into its eye. At best you'll partially blind it and it will stomp around in pain, squashing you in the process. In the hp-less Nevercast system, here's how to slay the mighty Dragon.
1) Ok, Dragons don't cast spells. That's just retarded. They breathe fire on you and eat you and make life on the countryside a little more miserable than it already is.
2) If you are caught in the middle of its fire breath or its tail swipe, you will die unless if you use an evasion to move away from the area of effect. If you are out of actions, you are dead. This is because the effect of the attack far surpasses the effect reduction of any sort of armor you may be wearing, and the great surface area of the attack will prevent any type of defense other than evasion.
3) Most of the dragon's body will be completely invulnerable to your physical attacks (unless if the Dragon is small enough), because its effect reduction score will be too high.
4) Therefore, the methods which a party must utilize in order to kill such a creature would be to maintain a healthy distance until someone has an opportunity to climb onto it while the other characters distract it (and probably die), and then cut arteries, blind it, or attempt to penetrate the dragon's skull with a powerful melee attack. A wizard could levitate, confuse the dragon, slow it down with offensive spells, or cause structures to fall on top of the beast.
((Combat example to be posted later on.))