Agree with all the above!
We have a run of Pax wardrobes and each one has a rail with a shelf above the rail and drawers in the bottom half, except one single (50cm width) which is just a full height rail to store long dresses and tall boots at the bottom.
Some cupboards have more drawers and we put shorter clothes on the rail, some have fewer drawers and we put longer clothes on that rail.
We have hinged doors so cannot have a drawer at the bottom of the wardrobe due to hinge position, only realised this late on. instead we have either a basket or the pull out shoe rack at the bottom, as either of these work ok with the hinges. The baskets are not as good as the drawers, don’t open and close as cleanly, so would definitely use drawers apart from at the bottom.
Yes to the pull out tray, perfect for jewellery, sunglasses and all those other small bits and bobs. We have the flat Komplement felt trays for jewellery etc too.
Yes to the Komplement felt boxes for dividing up drawers, especially useful for underwear drawer.
Consider how tall you are and how long your clothes are when deciding where to place your rail. You may find you want to install the rail down a bit from the top and have a shelf above it. If so then the Skubb boxes are useful for this as they fit the shelves exactly - easier to pull down the box and look inside than rummage on a high shelf. we use the Skubb for travel clothes/occasional accessories/ out of season stuff.