Like others said, you should check out the Giant forum for people who are more familiar with this bike.
I think the Trance is a great bike, certainly within the top-tier of big-brand XC FS/trailbikes. The value that they represent is terrific, especially from the Trance 2 down. The Trance 1 is still a great value considering the racy components that come for the price.
I would have to say that the frame (I bought just a frame) strengths and weaknesses are:
Strength:
1. Lateral rigidity
2. Pedaling efficiency
3. Suspension quality
4. Great value for the money in both bike and frameset form.
Weaknesses:
1. 0.5-0.75 pound overweight
2. Soft paint
One thing that has to be noted is that the Trance is air-sprung, so it will feel different from some other frame that is coil-sprung. I've also noticed that my RP3 feels much plusher after being broken-in for a few months.
Looking at your past bikes, I need to comment on this:
The Fisher Joshua and Trek Y-bikes were bob monsters despite the URT. This is primarily because of a failure to understand the URT concept combined with 1) the need to skirt Castellano's patent and 2) the misguided lowering of the main pivot in an attempt to "improve" URT performance by making it more "active." They failed to understand that putting the pivot significantly inboard of the path of the pedals means that every downstroke (which is more likely than not stronger than the corresponding ustroke on the other side of the cranks) levers the swingarm upward, with the pivot as the fulcrum. They were simply bad designs.
The Giant NRS should not have had ANY brake jack. This is because that particular bike deviates from suspension norm in that it needed to be run with NO suspension sag. In other words, you should mount it and it should not compress whatsoever. If it is not compressed, it should not have room to extend, hence no "brake jack." It was designed explicitly to behave like a hardtail the vast majority of the time, as it was first and foremost an XC racing bike. This should have been explained to you when you were considering the bike. It was a good design for its intended usage.