I've done a couple FP deployments. I love it. Not sure who told you Nexus "isn't as fast as it could be". It's all wire-speed/non-blocking other than L3 on the 5K, which people shouldn't be doing anyway.
Post any questions you have.
I've never heard anyone define QoS by how many groups of traffic are touched. "QoS" is just a group of technologies used to treat subsets of traffic different from other subsets of traffic. Policing, shaping, marking, etc, etc, fall under the QoS umbrella (I feel like a broken record). Saying...
A router isn't going to show you how many TCP connections are flowing through it unless you enable a stateful firewalling process (CBAC, ZBF, etc), which wouldn't necessarily be recommended - also, I don't think the 6500/7600 supports it.