I understand concerns with necromancy - it's generally considered to be a terribly evil magic, and everyone brought back in this way hates it and wants to die (in most stories, anyway). There are very few stories where a necromancer is also a good person. I can't think of any, anyway.
I knew I was forgetting one example! Some people would consider what Jesus did to Lazarus to technically be a form of necromancy. I think that that is almost as unfair as referring to Jesus' own resurrection as 'zombie Jesus', but the point being, there is one story where it's apparently right and good to bring someone back from the dead....but note that Lazarus gets to go on with his life as a normal human being, and is not an undead slave or anything.
But yeah, in general, necromancy is bad, and fiddling around with people's souls and their eternal fates is not a good thing.