The Player's Handbook page 118, when describing the School of Necromancy subclass feature says:
Most people see necromancers as menacing , or even villainous, due to the close association of death. Not all necromancers are evil , but the forces they manipulate are considered taboo by many societies.
There is room in the novels for non evil necromancers but you will be working uphill to convince others you are good.
Remember, that most of your necromancy school special abilities are focused on creating or working with the undead. So unless you work out with your DM alternative school features, or totally ignore your class features (in which case why would you pick necromancy to begin with?), you will be creating undead which most view as evil incarnate, and goes against many deities including the FR God of death Kelemvor. But you can always be the drizzt of necromancers.
The following are possible replacement abilities you might want to request from your DM:
School of Affable Necromancy
Grim Harvest: This can probably remain as is.
Undead Thralls: Instead of Undead Thralls at level 6, perhaps you can replace this with Revive the fallen, raise monsters from unconsciousness that were recently made unconscious and have them under your control by trapping their soul but keeping their body a bit alive. This mostly requires make a new version of the "animate dead" spell.
Inured to Undeath: Instead Inured to Undeath at level 10, perhaps keep the power the same, but change the name to Resist Undeath and the flavor so it's an overwhelming amount of life flowing through you that helps you resist the undead.
Command Undead: Instead of Command Undead at level 16, you might ask to change this to Release Undead. Same effect but instead of controlling them you release them from their state, and their soul does some action for you as a sign of gratitude. The soul is then sent to the realm of the dead.