Do you have any other equipment besides your soundcard, like a mixer with preamps and phantom power?
First off I'm far from being a mic expert and I do not do vocals (you're welcome).
I normally only mic guitar cabs on occasions and maybe an acoustic guitar. But the thing with USB mics from what little research I have done is you are stuck with it, it has it's own analog to digital converter, etc. You can not upgrade unless you buy a better USB mic.
For about the same price as the better USB mics you could get a USB audio interface like a Focusrite or Presonus AudioBox and a mic like the old standard Shure SM58. And later on down the road you can update the mic, or get a better mic preamp or interface. There is more interchangeable parts.
Do not get me wrong, I'm not trying to talk you out of buying one. I just considered it at one time and thought about upgrades on my little home studio down the road.
But who knows, maybe USB mics are the future with the way technology is advancing.Good luck.
BTW. If your MRS. says anything just tell her you was going to buy one of these,https://www.americanmusical.com/Item--i-NEM-U87AISETZNI-LIST
So you saved her $3300.