(Note: although I know of Vampire Survivor, I've never actually played it)
I had a good few minutes of fun with this, I enjoyed herding around the large group of enemies as I slowly went from overpowered to overwhelmed as the difficulty started curving upwards. :) As for negatives, it wasn't really clear to me how the enemies were different, and what my upgrades and attacks actually do, so I was kind of maneuvering around randomly, just trying to make sure I don't touch anything but the powerups (which were at first also difficult to discern as they kind of blend in with the rest of the artwork).
The audio was unfortunatly quite jarring so I had to turn it way down.
Overall a great effort for a beginner!