Hi there Le Mons hater,
The boolian add-on does not work for me either.
I went to your page @ imgur. For a base-mesh you have an awesome start. Have you taken the time to study real pro’s with what kind off a base-mesh they start ?
Take a look at this time laps video. As you can see, there is nothing wrong with your base-mesh.
If you are not good at sculpturing yet you can leave details, like fingernails, when you are doing the re-topology.
Here is a free video how to model fingernails.