Just for fun, who has taken V-human and taken magic initiate for more cantrips or taken it as a feat later on? Which class magic initiate do you take? What cantrips do you usually take and whats the first level spell you usually take? 

I like to go Cleric or Druid for Guidance and Healing Word for a emergency heal for the main healer if they go down.

Or I just go Wizard again for whatever I didn't have room to initially pick up like Prestidigitation or Mending and the 1st level spell will probably be Mage Armor because it can potentially last the whole day.

I’ve taken it twice. Once as a Moon Druid to get Mage Armor which really helps since most beasts have terrible armor classes. And once as a Warlock to make it possible to pretend to be a Wizard. With Pact of the Tome, Magic Initiate, and Book of Ancient Secrets a Warlock can fool a lot of people, including experienced players, into thinking that he’s a Wizard. 

Question: can you use magic initiate to get more spells in a class you already have?

Yes, that’s a common use of it. Especially for casters with limited spell selections. 

I have multiple times, once I wanted to cover all the element controls without really eating into my core cantrips too much. I think I took control flames and old earth with it, shape water with normal cantrips out of the gate, with you know an attack spell, and prestidigitation. Eventually got gust

Mage Hand, Prestidigitation, Mage Armor. 

Staples for any arcane caster, particularly Sorcs or Wizards. I always want these and using the feat means I also don't have to use a spell slot for my mage armour protection.