Hi Weseixas - you yourself listed several in one of your previous posts, and I already mentioned the Altec A7's, which I happened to hear again today as a matter of fact (my uncle owns a pair). Properly set up and driven with tube electronics, they cannot be beat for dynamic range, not only on the loud end but also and in fact particularly on the soft end; they image wonderfully, and most definitely come closest to a life-like presentation when we are talking about trying to reproduce the sound of an orchestra in a great hall. If that is not your cup of tea, that's cool with me. There are many fine speaker designs, some of which sound better for certain things than others, and one's taste in music will heavily influence your choice. As I said, a great many professional orchestral musicians who are also audiophiles feel that the old-school approach has never been equalled for reproducing the sound of an orchestra, let alone bettered. Much of it has to do with your third priority, "sounds natural." Horns driven by tubes do an astounding job of recreating acoustic instrumental timbres, and also do a damn fine job on the human voice as well. Altec, JBL, Klipsch - even if they are not your cup of tea, you have to admit they are extremely successful designs that have survived longer than pretty much anything else in the audio world.
