My honest opinion?
Do away with the pseudo-medieval lighting if you don't play entirely diceless.
Especially when playing long sessions, you will either need a lot (and I'm talking about 30-50, depending on room and table size) of candles to provide adequate illumination, or the strain on the eyes will just become too great and keep you from having fun. When everyone's squinting at their dice rolls just to try and guess what faces have come up, the result isn't a better roleplaying mood, it is annoyed players and GMs. What I would go for, instead, is indirect lighting. Ideally, each player has a dimmable lamp near his or her seat and can adjust brightness as needed (e.g., more when combat comes up, less when everyone's just roleplaying a conversation).
With regard to the OP (because I don't want to derail this thread):
What worked extremely well for me was taking a cue from serialized television programmes and coming up with a 'theme' music for the PCs, major organizations of the setting, primary antagonists and certain locations whose uniqueness I wanted to convey not only through description, but through music/sound effects, too. This method only works if you have recurring characters and locations, of course - no sense in wracking your brain for a possible evil theme if the relevant character will in all likelyhood die in the first encounter.
A nice perk of using themes is that it allows you to subtly foreshadow connections between certain characters or events. For example, you might play the Faction A theme during a scene when the characters haven't interacted with that faction yet, and then play it again, later, once they meet up.