The best, most practical, and helpful travel gadget or tool I’ve purchased is the Eagle Creek Pack-it Garment Folder.
You can have the cheapest suitcase, a duffle bag, or no suitcase at all (I’ve tossed it in my shoulder bag overnight trips), and this garment folder will keep your shirts crisp and unwrinkled. Nicely ironed shirts matter.
Iron (or dry clean) your shirts beforehand, fold them using the included folding card, and then pack. Once you arrive at your destination, unpack your shirts and hang them up. Putting your shirt of the day in the bathroom while you shower is just enough to steam out the creases.
I’ve purchased a lot of silly travel gear and bags over the years. But nothing, absolutely nothing, is as important to me when traveling as this garment folder.