Yes, your Merinos bag will flop over. That is the nature of Merinos.
Pompei is great for structured bags, but I'm not sure what colors are available. I know marine blue was available in Pompeii at one time. Vachetta is another stiff leather. Depending on the color, it can be a little more casual than Pompeii(and nappa) because some colors scratch easily(makes it look more worn like Frye bags). The only blue in vachetta is River blue which is a lot darker. Nappa is also one a lot of the ladies like for structured bags. My one and only nappa bag is not structured, so I have no personal experience in that regard. Nappa has a slight Sheen, but it's not shiny in the least. Nappa easily works with a suit for the office or Jeans and a Tshirt .

Let us know what you end of going with!