Nail said:
Just in case there are any newbies out there still reading this thread: This is what's called a Flame War, at least by ENBoard standards. (Usenet et al. are worse, trust me.) Note especially the lack of new points or real discussion on either side.
Hmm, I just got to this thread, and I really don't think it bears much resemblance to a flame war. Moreover, there are several new points, or at least new variations on previous points, herein.
Grog's argument is elegant, concise, and seems to hold water; IMHO, however, it doesn't apply with particular force to haste. There certainly are "must-have" spells (invis, dispel magic, poly other) that would be valuable at any spell level, but there's a major difference between these spells and haste: They don't scale with the target's power level, whereas haste does. Let's look at haste's effects, shall we?
+4 dodge bonus: The only spell I can think of that grants this; a lovely AC bonus that stacks with all other AC bonuses, making it hugely useful both to mid-level characters (to whom +4 is a big AC boost) and to high-level types (who will likely have maxed out their armor (+enhancement), deflection, and nat armor bonuses with equipment and other magic, and whose dodge bonuses will stack with this anyway).
Extra partial action: It goes without saying that this becomes a bigger and bigger bennie with higher levels. A fighter can move and attack an extra once to three times depending on level (or more with two weapons), a rogue can move and full SA (both attacks and damage scale up with level in this case), and a caster gets the equivalent of Quicken Spell for free on one spell per level. Note that the latter is the ONLY means in the game, short of epic levels or weird PrCs, that allows casting of multiple 6th-9th-level spells.
Effective free casting time: This is huge at high levels. A high-level caster in a combat situation simply isn't going to waste a single action firing off anything less than the best spell he has, unless the threat wasn't a big deal to begin with (in which case it's likely that the caster isn't even going to need to act!). Once more, haste is the ONE low-level spell that breaks this rule (with the rather sad exception of feather fall and certain 3rd-party sourcebook spells).
With all this in mind, I'd either remove the +4 dodge bonus or rule that haste grants only an extra move action, which solves the multiple-cast problem, but not the move + full attack problem; I consider the former more serious than the latter, though. Otherwise, make the spell 5th level, and its mass version 8th; IMHO, it's worth such a serious spell expenditure, and casters will feel the hit all the way through high levels.
Conversely, haste also can be thwarted easily by use of the slow spell. If you raise its level or blunt its power, I'd suggest altering the effect of slow from automatic countering and dispelling to dispelling on a successful caster level check.