Nifft said:
First off, area damage is something only a Wizard can do well. If you need to clear a room of kobolds, fireball is your best option. Direct damage -- especially area damage -- is very useful from level 5 through 12. Below that you're about as useful using a crossbow or Reserve feat, above that you're better off just ending the fight with a big nasty control spell (either a save-or-die, or a denial spell like solid fog).
Secondly, slow is excellent against multi-attackers, but irrelevant against a bunch of low-level foes in close quarters (e.g.: a room full of kobolds).
Third, some Wizards will never need dispel magic. Its utility totally depends on the DM throwing buffed antagonists against you, or enemy spellcasters. At 5th level I'd scribe a scroll of dispel magic, and then don't prepare the spell until you have used the scroll.
Fourth, magic missile can automatically hurt things which are otherwise quite difficult to hurt, like insubstantial monsters in shadowy illumination (e.g. Shadows). Some of these insubstantial things drain ability scores or impose negative levels, so a long fight may indeed kill someone, even if you've got two healers. It counters and dispels mirror image, it ignores displacement, and it shoots through schools of energy resistances. It's honestly kind of broken, since it's the only 1st level attack spell which improves after 5th level... at 5th level it's pretty balanced against lesser acid orb, but by 9th level it outclasses the alternatives.
Hmm... partly agree and partly don't.
1. How often will a roomful of Kobolds be a threat to your party at all once you hit 5th level? Now leveled Kobolds would be something else, but then your Fireball will only do so much. Also, highly circumstantial. I'll find a way to make Grease or Glitterdust useful in every fight. Fireball? Only in special circumstances. I'll give you useful at levels 5-7, but at level 12 (!), I'd rather be doing something else. I can sling 6th level spells by that level, how is 10d6 with a save for half (which most enemies will make at that level) going to compare? Not to speak of fire resistance, which starts to become kinda common once you hit mid levels.
That said, I do advocate direct damage spells from time to time. Their effects stack with what the rest of your party is doing, so that's synergy right there. However, you're the guy the party looks to when less generic answers are needed, so you should concentrate your efforts more on those things. Area damage can easily be done by a big burly guy with a reach weapon and Combat Reflexes, by the way.
2. Slow is all around useful even against many attackers - because it slows quite a few of them down. Even if they don't have more than one attack, it's very useful, as it basically turns them into Zomcies: no move+attack, only move. Oh hey, I moved too! Now they have to spend their action moving again and can't touch me! And all the while their base movement is cut in half, so even a Gnome can run circles around them!
3. Dispel Magic is not only useful against magicked-up enemies, it's also important utility in dungeon surroundings or even in political intrigue campaigns or urban murder mysteries. Sure, it's DM-dependent, but show me a DM who never incorporates magical challenges after level 5! I'd rather not rely on a scroll for things that are caster level dependent. Nor do I like to lock my wealth in a scroll that needs max caster level.
4. Magic Missile is one of the best direct damage spells out there, nobody will deny that. I still thing direct damage is
usually better done by other people. Sure, if that Shadow pops out of the wall at low levels, Magic Missile comes in handy. But how many of those do you need to kill the pesky thing? A Shadow has 19 HP on average, at CR 3. Your 3rd level Magic Missiles will deal an average of 7 points of damage. You probably won't have
three Magic Missile spells memorised (unless you're a Sorcerer, but that's a different story), so a Magic Weapon spell would have been a better investment.