Shar is one of the most evil gods in the D&D pantheon. Way worse than even Lolth.
Setting aside the rest of what you say (some of which has merit, especially the last line), this is absolutely not true. Shar and Lolth are both evil deities; Shar is a Neutral Evil greater deity (the goddess of darkness) while Lolth is a Chaotic Evil lesser deity (the Queen of Spiders and goddess of the Drow, and once the elven goddess of destiny). You cannot directly compare how evil they are; but Lolth has certainly perpetrated much more evil as the tyrannical ruler of the Underdark.
Also note the following definitions as per the Player Hand Book:
Neutral evil (NE) is the alignment of those who do whatever they can get away with, without compassion or qualms.
Chaotic evil (CE) creatures act with arbitrary violence, spurred by their greed, hatred, or bloodlust.
Honestly, if I were forced to pick which was the "more evil" alignment, I'd pick CE.
And honestly, Lae'zel is the very definition of Lawful Evil.
PHB: Lawful evil (LE) creatures methodically take what they want, within the limits of a code of tradition, loyalty, or order.
