Personally, I'd complain about a different 3rd level spell before I'd complain about Haste. Protection from Elements. Sure, it doesn't allow you to double your output in spells - but it will keep you intact to cast them, vs. any enemy that uses high - power elemental attacks - and these attacks aren't always minor. The CR 7 pyrohydra could do 18d6 fire damage in a round, for instance, but a 5th level casting of ProtElements negates it entirely most of the time.
Now, don't mistake me; I don't think Protection from Elements is overpowered. I do think it's powerful. It gives access to an ability that you normally wouldn't have - near immunity to an element. It's very nearly an absolute defence. The reason it's third level is because the designers of the game mostly agreed that that sort of protection is appropriate to a 5th or higher level party. I think the same goes for Haste.
Haste shows up at 5th level. What it does for the mage is allow - for a short period of time - a doubling of attack rate. At 6th level, Fighter-types get something very similar - an extra attack. It's less likely to hit than their first, and it can't be used in every situation - but it's always available, not just for 1rd/level, and fighters don't run out of spells/day. Doesn't seem all that bad to me, at this point. Yeah, later on Haste lasts longer, mages have more spells, and more powerful spells; but other classes have more attacks, more HP, and better defences than they had before, too.
As for the frequency of use - in any situation where an elemental - using Big Bad might show up, namely anywhere there's a wizard, a dragon, or a demon, or anything else that can hammer out powerful magic, ProtElements is pretty much required - at least for the party members without all the HP of a fighter of barbarian, anyway. The same can be said for just about any defensive buff in the game. Endurance, anyone? And what about the Cure spells? Are they overpowered because they see so much use, or is it because they are the best way to access a particular ability - one which shows up at low levels because it is of appropriate power in low level gameplay?
And that is my opinion.