I'm a newbie to RVing but have just gone through the same situation. This is what I found:
1,000/10,000 WDH is over kill but the cost is not that much greater than the 600/6,000. If any time in the far future you may end up with a larger/heavier TT your set.
I had to set my sway bars up myself (no drilling or welding required with an Equalizer). It was easy. 15.5" sounds a little low. My 2720sl was set at 20-21 inches.
The hitch was set up by a RV dealership as well as my Prodigy P3 controller.
And again Bill has an excellent post on your subject.
I know it's a bit frustrating being out there on the edge but you'll get through this
