The questions may sound a bit theoretical, because I use my own app for my shopping and can therefore only point out the differences (or what I miss about the Migros shopping list).
However, the Migros app would be a very interesting option for me if the shopping list could be loaded onto the scanner, thus eliminating the duplication of Migros hand scanner + own cell phone/postcard.

-- 1. sorting by category is ok in itself, because you shop according to a self-defined route. However, the order of the categories should correspond to this path, which in most cases starts with vegetables/fruit. Since not every Migros is set up in the same way, the branch should be selected first when sorting.
-- The alphabetical order of the products is ok, but I am bothered by the somewhat broad individual terms within the categories. For example, the term cake: I expect cakes and not Cucina&Tavola, children's toys, articles from Do+It Garden etc. which are not to be found under the category Bakery,Confectionery&Baking anyway, i.e. not even in the supermarket. So, after making my way through hundreds of items, I finally end up with the Tyrolean cake and can add it to my shopping list.
--3. Such an approach (fighting my way through 100s of items) may work if I make fixed shopping lists and always shop according to the same routine, but not with spontaneously created shopping lists. I miss a kind of favorites list where you only see the items that you have previously selected as favorites. It should also be possible to assign these favorites to another of the predefined categories.
--I find the terms total/savings/cumulus points superfluous for a postcard because they are not complete anyway. I can see the total on the scanner, the actions in the same place on the orange marker and the cumulus points are only visible after the purchase because of the 20x etc.
--5 Own terms for items that are not listed but are stored in a personal catalog. Catalog are stored

In short: Compared to my own app, I miss:
-- Personal catalog of terms that can be assigned to categories
-- Immediate display of the relevant articles, so that you are at your destination after just 3-5 letters
-- Simply tap on these suggestions and take them over
-- Do not put the display in idle mode (dark background - white font) for shopping list
-- own sorting
-- Move individual items from one list to another

I know.... a lot of wishes ;-)