You will probably be looking for a quilt/duvet/duvet as well as a quilt cover to cover it, since this way the duvet will stay cleaner longer and it is easier to regularly wash just the quilt cover. It does not really matter how the material of the duvet itself feels against your skin, since you’ll only be touching the quilt cover while you sleep. So for the duvet, you will want to focus on a filling material with the weight, warmth, comfort and practicality that suits you. We’ve written about the most common kinds in our article: Which duvet is right for me? You mention the duvet being firm, luxurious and comfy. This would imply one of the heavier, denser quilt materials such as wool, but if you are a warm sleeper or your room is warm at night you may prefer Microfiber or Cotton.
As for your wanting no flat sheet, feel free to avoid bed sheet packs which include a ‘flat sheet’ where possible. You will still want a sheet set which includes the fitted sheet which covers the mattress and enough pillowcase(s) for your pillows. We at BedLinenOnline have ‘Full Sheet Sets’ which do include a flat sheet, and ‘Fitted Sheet Sets’ or sometimes ‘Combo Sets’ which do not include a flat sheet. They are sometimes confusingly named, but the packaging/website should always let you know what is included in a pack. If you’re in a shop, ask for ‘sheet sets without a flat sheet’. If you find a sheet set you really want that only comes with a flat sheet, you can always simply not use the flat sheet. Your ordinary quilt cover set will include a quilt cover and pillowcase(s), both required. You may not need all pillowcases from the sheet and quilt cover sets, instead opting for whichever feel better against your skin or if they all feel great, whichever look better in the bed ensemble.
As for material, you will want cotton or bamboo sheets/fibres, since microfibre and polyester (even polyester-cotton blend) will not feel as good. Cotton sheets are by far the most common, and would almost certainly have been used in your hotel. Thread count (abbreviated to TC) is a good indicator of how smooth cotton sheets feel, so if you want a luxurious experience we recommend going for plain cotton sheets with ~375 TC+, or Egyptian Cotton of ~500TC+. Lower thread counts than these may not be smooth enough, and also may ‘pill’ when washed. Higher thread count sheets will feel heavier, but this is irrelevant since you will only be sleeping atop them. We explain thread count in a lot more detail in this article. This still leaves you with a choice between Egyptian Cotton vs. Bamboo Fibre vs. High TC Cotton. Egyptian Cotton can have higher thread counts than ordinary cotton without being as heavy due to the type (specifically length) of cotton used to make the sheets. This is why Egyptian Cotton is generally seen as superior to ordinary cotton sheets.
Quilt covers tend to come in bright, colourful designs, but plain quilt covers are also fairly easy to find. Make sure your quilt cover is not polyester or microfibre since you’ll be having it against your skin, and those materials are less breathable. Also, if there is any embroidery on your cover, you want all of that to be on the top surface of the cover so that the side touching your skin is smooth and plain. Now that you’ve eliminated Microfiber and Polyester, Cotton will be the most common material. We recommend 375 TC Cotton Sateen or 500 TC Egyptian Cotton if you can find quilt covers made of them. Go too high in thread count and you will risk having a more weight on you, and go too low and the material will feel coarse and might even be in danger of pilling.
You mention a big quilt, which brings me to sizes of duvets and mattresses. The five most commonly used sizes in Australia are Single, King Single, Double, Queen and King. These are in order of ascending width – so King is the largest from side to side, and single the narrowest. Length from head to foot of the bed is also important, and of these King Single, Queen and King are all the same length (203 cm), 10 cm longer than Single and Double beds (193 cm). These are only the most common sizes, and there are mattresses in other sizes. It is generally more comfortable sleeping in a larger bed, but you should be able to tell what size most closely matches your hotel bed from sight. Queen Size is the most commonly preferred bed in Australia, as it can fit two people quite comfortably.
All the best to you searching for your perfect luxurious bed!