Artists have a ton of options in brushes today. In my experience, there is no "right" brush. I use different types of brushes for different subjects and to achieve different effects. When finishing a painting,the best brush for me is no brush at all, and I complete a painting with finger touches and slashes from the palette knife.
In my studio I prefer the interlocking bristle brush for most paint applications. These brushes are made by hand-orienting the bristle hair toward the center of the brush, so that when loaded with paint, it holds a point and doesn't splay out. That said, I also keep an assortment of sable watercolor brushes that I use to apply thin glaze layers of oil paint to a mostly dry painting. Don't be afraid to discover new ways of applying paint by using brushes in unconventional ways.