The principal requirement of a field that will be faceted on is that it must be indexed; it does not have to be stored. And for text fields, tokenization is usually undesirable. For example,
Non-Album\ Track appears in
mb_attributes.txt with the space escaped with a
\. Otherwise, faceting on
r_type would show tallies for
Track separately. On the other hand, tag-clouds, hierarchical faceting, and term-suggest are faceting use-cases that handle tokenization just fine. Keep in mind that with faceting, the facet values returned in search results are the actual indexed terms, and not the stored value, which isn't used.
If you have conflicting indexing needs for a field, which is not uncommon, you will find it necessary ...