From what I can tell from the introduction and initial HN thread Bel is an academic exercise in developing a programming language by focusing on axioms rather than implementation. Also:
I think the point of a high-level language is to make your programs shorter. All other things (e.g. libraries) being equal, language A is better than language B if programs are shorter in A. (As measured by the size of the parse tree, obviously, not lines or characters.) The goal of Bel is to be a good language. This can be measured in the length of programs written in it.