So, you might be saying "But that is very little damage" but... Then you calculate Magic Missiles. Which automatically hit, and hit multiple times... and they all get your evocation bonus.
Necromancy is something I'd want to see in play before I write it off... But there are certainly quite a few ways to make this shine brightly. For example... Get a Beholder Zombie. Full stop actually...
Oh, like I said, Evocation was a solid choice before a bunch of aspects of it got nerfed. The bonus damage on every projectile/ray is one of the parts that didn't, and it pretty good as blasting goes, but...
You're still a 5e Wizard with heavily limited spellslots who has now dedicated their entire build towards doing something that any martial character can do all day every day. I'm not
certain, but I think they even nerfed the good ol' Flaming Sphere -> Pyrotechnics combo by not distinguishing magical from nonmagical fires in the latter's description.
Being a necromancer in 5e flat out sucks. Here's why:
1. Your spells are limited to
small/medium creatures only.
2. You can't animate/create undead in battle.
3. YOU HAVE TO CAST THE FUCKING SPELLS EVERY DAY TO KEEP CONTROL. Those are 3rd and 6th level spell slots respectively that you are
never going to get to use (or, for a change,
all of your 3rd-9th level slots you'll never use if you go full bore), in exchange for some mediocre Medium-sized minions. The more undead you have, the fewer spells you have (and here's hoping you're never locked up or knocked unconscious longer than 24 hours, eh?).
4. I did the math a while back, and what it comes down to is that even at 20th level, even giving up as many spell slots as possible, even with all of your School features, you're still commanding at best a platoon worth of shitty undead and a relative handful of slightly better undead. It's faster, cheaper, and more effective to
hire minions.
I was shitting on Evocation now that it's half-useless as opposed to decent, but that's still a better choice than Necromancy. Playing a 5e Necromancer is like playing a deliberately unoptimized Healer in a campaign where the rest of the party can heal themselves and rarely takes damage: your skillset is narrow, removes the potential for doing anything else, and is rarely useful.