Glad to see this thread.
I trade the NQ largely because I've found that it's amenable to predictive analysis. It's price action produce market profiles that fit into vey nice little jigsaw puzzle peices. And so, for example, I felt that it was reasonable to assume that today's price action would be bounded by the red horizontal lines on the accompanying chart. Thereafter, intraday analysis gave direction and quite a few
entries and exits targets.
I also like the fact that the NQ seems to be less "nosiy" than some of the other e-minis. Take the ER. It has about the same daily volume as the NQ but far more ticks (trades) per day. This suggests that there are more small lot ER trades which tend to produce more whipsaw action at pivot highs and lows. Trading is tough enough as it is and I prefer not to have to deal with this noise.