While 35/1.8 would have been nice (I have the FA31 so it's moot to me anyway), I think the grievances are a bit unjustified:
1) The FA35 was F2. Yes, and it was more expensive even at $300 (much less $450). So now you get 1/2 stop slower and about 35% cheaper. Pretty fair deal.
2) The Nikon is F1.8 for the same(ish) price. Yes, but Nikon sells tons of them (certainly more than Pentax would have sold of its DA35 even at F1.8) and benefits from economies of scale. Pentax probably cannot afford a loss leader, or at the very least, lower margins.
3) The Nikon is AF-S. Yes, but partially because entry level bodies don't have a screwdrive. It's true that quickshift would have been nice, but the majority of the target buyers probably want just AF anyway.
4) The Nikon is better built. Yes, but it sounds like people are picking their comparisons. Everybody is OK having a crummy-built Canon 50/1.8 because of its low price and that is brought up when comparing to Pentax. Finally Pentax offers a DA-L which probably isn't half as crummy as the Canon 50, and now we're saying the Nikon is higher quality.
I think most folks would observe that the only way to get "fast" apertures is to go big (DA* and FA Limited) or go old (old used lenses, FA Limited haha). The only DA lens faster than F2 is the 55. All the DA Limiteds are slower. It's not good when Pentax users feel the competition is better, but Pentax has made their offer on an affordable normal and if it's not good enough, users will leave and that's the way it is (sadly). Personally I have a friend with an F50/1.7 who likes the red version