Hi, runner22, and welcome!
I'm sure one of the lovely ladies here who owns a LMM can chime in, but I believe how structured the bag is depends on the leather you choose. The crash leathers and the matte leathers tend to soften up quite a bit with wear, but I'm not sure about degree of "smooshiness". I have a matte dark grey LM and it still has structure, but certainly much less structure when compared to when I first received it. If you look through the photos only thread, you may find some examples. Certainly, "out of the box" the bags are more structured.
Re. which bags she will continue vs. discontinue with the introduction of her Fall line, we are still waiting for Ashley (Jackie's right-hand woman!) to get back to us on that. It appears that no style is completely out of the question, provided that Jackie has the leather available and we get a minimum of 10 requests for the exact same bag. Jackie said she would be willing to stretch it to a minimum of 6 or 7 bags, but understanding that bespoke orders cost her money as well as slow down production, it probably makes sense that this is the direction she is going in.