Nekros is about Necromancy, nothing to do with the Grim Reaper. And technically not really a master of death I'd say, but that is probably a matter of perspective. Master of Undeath imo (Which is often perceived as the highest of sins among followers of Death).
Imo, Nekros lacks a lot. Sure he WORKS, but he isn't fun. Imo, Terror is a horrible ability, both boring, and often times counter-productive to the goal (Unless you take an augment that simply slows them). Soul Punch is practically useless (The rework is decent though, but still not what I'd like to see personally). I also