I prefer the varied approach that showcases multiple artists which allows for different styles. The consistent house style is feast or famine. One thing that I couldn’t stand was the 3e spikes and buckles artwork but had to live with that. On the other hand, I’ve said the 3e Forgotten Realms book was a masterpiece of design and art.What about you? Do you think an RPG should have a consistent art direction?
Edit: However there is a limit. I saw a book recently that had some gorgeous detailed artwork paired with something that struck me as very childish webzine style artwork and the two just didn’t mix.