No body is saying that cursing is obligatory. Thus my arguments prove to be correct. And yes “noble companions” are not evil doers but those who were not noble ones, can be, simple is that.
As for your personal notion that cursing anyone is un-acceptable then you have right to hold personal views but for Allah this isnt un-acceptable act since not only he Himself has done it but has also involved his blessed Prophet [s] into this act. [Again referring to Quran].
As for Ahlulbayt [as] cursing anyone, then I can present references wherein Imams of Ahlulbayt [as] did indeed curse the evil-doers but I wonder whether such refs will be accepted by you.