I stayed there for my birthday weekend this past October and found the rooms surprisingly dowdy and the food overpriced and not very interesting. The location was great, but I wished we'd just stayed at the Hotel Santa Fe which is a bit more generic and slightly more out of the way, but cleaner, better maintained and still walkable to everything. Maybe the new chef came later.
Not in probably five years and I don't even remember if it was the same place back then. I don't know that I've had a conversation about Luminaria with anyone who's eaten there - it's certainly never one of the places that comes up as a "mustn't miss" conversation. I'd be curious to hear your take if you go - some of the TripAdvisor posts were good, IIRC.