A question, what do you love about music? If you can figure out how to quantify this, that will go a long way to helping you choose a path.
I don't know what kind of music you play, but it likely has an influence in this. I'm a drummer myself and if equipment can't be articulate in the bottom end and provide correct tone on acoustic drums, I'm not interested (no horns for me). Maybe you are a bass player and you want something that "swings", so SET might interest you. Whatever the case, knowing what moves you will help.
Bottom line, don't think about a piece of equipment, think about what you want the total package to deliver. Listen to as many systems as possible and seek something that makes you sit up and take notice. Then figure out how to get your first piece of it. For me, I started looking for an amp and ended up with a pair of speakers (ProAc Response 1SC) that have lasted multiple amp and other equipment changes. That vivid sound grabbed me and i new that was what I wanted - even if the total package I heard was 10x what I could spend at the time, I knew the path I wanted to peruse and got the biggest piece first.
Lastly, I know you said you wanted room filling sound, but if you were to consider a nice pair of headphones and a head amp, you could spend $1,000 and get quality that will cost you $10,000 to match in a full setup. Worth considering.
Good luck.