Hi celestial and welcome to the beginners section!
Its wonderful to be in the position of having room for a large tank like that. Larger volumes of water are slower to change and give you more time to react as a beginner if a bad condition is starting to arise. You also get lots of choice while researching your stocking plans.
A couple of cautions spring to mind. The tank, stand and lighting lid are only the initial bit of hardware and if you really want to run a nice tank you will find that heaters, test kits, substrate, background and decorations are also necessary to varying degrees. Most importantly, as a serious hobbyist, you will want good filtration equipment and that can be quite expensive, so its very, very good if you get a chance to research that prior to an actual tank purchase (but of course that kind of restraint takes real patience!)
Here on TFF its often recommended that you plan a tank with at least "5x turnover" (which means that the full water volume would need to pass through the filter 5 times each hour) and depending on how serious you are about planting the tank there are planted tank enthusiasts who like to work with at least 10x turnover. The larger the tank gets the more significant the pumps get to achieve this and the more noise they make, which can also be a factor, especially if the tank will be in your bedroom. If you take a look at modern external cannister filters (more or less the top of the line for this sort of thing) by Eheim, Rena, TetraTec or Fluval, you will find the kind of media bed volume needed to do really good filtration of larger tanks. These filters can get quite expensive!
Another factor to think about, specifically with regard to the larger tank you've mentioned, is that most aquarists find it significantly more difficult to do their "substrate operations" (working with things at gravel/sand level) the taller the tank gets. I personally find a 17 inch tall tank to be a challange sometimes in this regard. Certainly not saying it can't be done, it just ends up requiring more extension tools, more patience, more time and effort.
So there are good things to be said about high quality setups in the 20G/75L to 45G/170L range that are fully fitted with excellent filters, heaters and lights. There are also good things going for the 55G/208L to 125G/473L range but the expenses do go quite a bit higher!
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