Spell-Slots in D&D

Part One: Dice ≠ Challenge. Part Two: Decisions = Challenge. Part Three: definition of issues 1-5.

Spell Slots in D&D add a lot of mechanical weightiness to the system, making the game very complicated. However, in the process, this largely avoids most issues. All but the weakest spells avoid problem 1. Only "save or die" spells really run afoul of problem 2. The only real resource-decision issue for the classic "Vancian" spell-system of D&D is problem #3: some spells are clearly the best option at their level.

A clever party can avoid issue 5 by resting often. Issue 4 only comes up if the PCs make camp after every encounter, which can be solved by a GM merely creating quests that have deadlines.

While individual spells could use a tweaking, the system as a whole has a certain (slightly complicated) charm. Rumor is things will be revised heavily in 4th Ed.