The Classic Black Hole Is Always the Best

Gravity is very strange compared to the other forces, as you were alluding to earlier. This thing diverges and actually goes to infinite density, if you give it enough time,. If you can cram a lot of mass in a small amount of space then you can get really close to it. And so gravity, left to its own devices, will always generate black holes. The electromagnetic force and the strong force give us structures that balance out gravity, at least for a time.