Looks real good.
Is that a sort of self-belt? Or does it just close on the side? Either way, it looks great! Mind giving your order number? It's got me thinking, I might just order my next Luxire trousers with a self-belt, if they're capable of making that.
The extra fabric just below the neck at the back is an easy fix by itself.
Your approach and analysis makes sense.
Adjustments related to shape of shoulders or any other fit issue is best addressed by looking at images of how the Luxire shirt fits. It gives us the idea of how to shape the yoke or what to change on the pattern for the next iteration.
Part 2 of your question:
I read a couple of times but was not able to bring myself to understand it. Please elaborate.
What I mean is that little 'book' of fabric samples to present possible options. Something like this:
It might be in different arrangement, smaller pieces etc.
We can make the fabric books. It will be expensive though.
We can also consider having a few set of books ready, which can be sent to a customer against a deposit and refunded once they are sent back.
Luxire Vs. Ambrosi - Fabric, stitching, fit, details - all look comparable. That too at a fraction of cost and a fraction of wait time.
It seems the pants are now maturing pretty fast.