Iku Rex said:
That's still far less damage than the character in my simple example will do on a single full attack. Throughout the battle. With no need to worry about SR or fire immunity.
1) No, it's more damage, for a standard action as opposed to a full round action. That was the example you used, so I am going with it. You want to become a moving taget, then I will happily add in quickend spells and occular the occular eye feat etc.. to the example. Your example was 50 or so. That's what we should be talking about.
2) You may need to worry about SR as your wraitstrike might well be cancelled by someone's SR (I am not positive how that would work). Also need to worry about DR. They balance each other. In fact, they were created specfically for the reason of balancing. And SR is *WAY* easier to deal with than DR, since it's one type. DR varies based on each creature, while SR can often be overcome by having a single feat (or two, if you REALLY worry about SR).
3) If you really need to worry about immunity, searing spell takes care of that, or energy substitution. In fact, if your tactic was just scorching ray, you would have that feat. I used scorching ray just off the top of my head. I could easily switch it to something else.
Furthermore I fail to see how the option to lay down the smack with spells
in addition to dominating melee is a
downside. (!)

If you want to claim that a wizard is useless in melee, compare him with other melee characters.
You had to devote your build to that tactic. It involves feats, armor, weapons, magic items, ability scores, etc... You do NOT get the same advantage of spells as a normal caster. It's going to be one or the other for you...not both.
(And scorching ray gives you a maximum of three rays, not four. +1 ray at level 7, +2 rays at level 11.)
Your right, it's 63. I was probably thinking of one of the feats that adds a ray, or fiery spell. Still, much more damage than you did with a standard action, for a LOT less effort.
Where do I begin?
The sword is not "otherwise useless". Remove wraithstrike and a well built melee wizard can still beat the crap out of just about any fighter-type. If it was "otherwise useless", that's beside the point since a persistent wraithstrike can be in effect 24/7.
If you are really a Gish, you don't have all wizard levels. You are not a 15th level wizard then. So, we are not talking about a "well-built" melee wizard. We are talking about a straight wizard who took some fighter feats and has a sword, but still has extremely bad hit points, bad saves, bad base attack bonus, and relatively bad AC. The sword is therefore not the thing you want to be investing all that money in, not to mention the other magic items you mentioned, none of which benefit your primary spellcasting stat or your spells or your hit points or your AC or your saves (all weak points of that build).
Power Attack is not "otherwise useless " at all - it's an excellent feat, especially for a character with lower BAB and a (potentially) high attack bonus.
You don't even have a potentially high attack bonus. Even with your polymorphing and magic items, it's still not anywhere near a comparable fighter. And, it's not useful OUTSIDE of this tactic, so again it's putting all your eggs in a sub-par basket.
Your argument seems to boil down to:
1. Wizards are useless in melee, even with wraithstrike.
2. Because of [1], no wizard will make an effort to be good at melee.
3. Because of [2], go to [1].
How about Wizards are sub-optimal in melee, and wraithstrike makes them simply adequate in that tactic. THAT is my argument. Wraithstrike doesn't result in an unbalanced character, it just makes melee a reasonable option for a straight wizard build where it was not a reasonable option before. But the end result is nowhere near "overpowered". Indeed, because you have to devote so much to it, I still think it's slightly underpowered.
Spot the flaw...
A 15th level wizard can easily do 12d6 + 196 damage every round (with haste effect activated) with the basic setup I posted. Remind me - which "out of the box players handbook spell" can do that for me?
First, you are not calculating that correctly I think. But more importantly, if we are talking about full rounds, I can do a LOT more with an out of the box wizard. 15th level is high level. TONS of instant death spells exist at that level, and modifications with metamagic and other spells and such will change the senario more, and adding in full round actions changes it even more. Those instant death altered spells will NOT be as potent with your build.
So lets stick to the example you set forth, and not change the example mid-stream. That's what leads to endless discussions with no point, as everyone is a moving target and will continually shift and posit strawman until someone just gets tired.