I'm pre-wiring and I just had to move the couch back in my plans, so I'm wondering if this is a good sound arrangement. Specific Questions: 1. Is the subwoofer in a good spot? 2. Are the side speakers too far back, or not far enough? 3. If I got a second sub, where should it go? Feel free to input any advice. The surround speakers are all Infinity satellites. I was thinking of upgrading the front speakers to towers.