I prefer a close balance. There are some really great mechanical elements appearing in Dragon these days, especially in the Class Acts feature, but I also really enjoy lengthy articles of flavour, like the Core Beliefs series which might have a spell or two, or a magic item, or a feat associated with the deity.
Actually, one of the best examples of the balance I love is the Demonomicon articles themselves: plenty of "fluff" on a demon lord's history and goals and relationships, but also a healthy dose of "crunch" in terms of a thrall prestige class, associated monsters, and magic items.
The only thing I might add to the Demonomicon format for general application would be switching out the thrall prestige class for substitution levels, alternate class features, or feats, as appropriate. Substition levels are excellent - they were used to great effect in the articles on the Sun and the Moon back in February.