Hm... Last time when I've heard sound in wow was early wotlk, since then any shitty spell sound didnt have acces to my earm with exception for boss fights (since Dragon Soul and Warlord Zon'ozz audio <3). Its Super-duper annoying. I probably never enable them again
I don't understand how some people play without sound. I use sound cues for so many things. As for a "charge" sound, it wouldn't be a bad thing for long cast-time spells. As long as it's not an annoying sound like Inner Focus. Ugh, I hate how IF sounds. It's pretty and shiny, but the noise is enough to make you use it even if you don't need the crit.
I like the sound effects, but I abhor most of the voiceovers in the game, so whenever I'm raiding, I'm usually listening to music with no game sound on. It is weird playing without sound but you get used to it.