If you want the old, bloated layout back so badly with custom tabs, you would probably want to know that there is already a community resource produced that replicates all of the built-in tabs in the legacy UI as closely as possible using custom tabs.
Layout is zero excuse if you actually bothered trying to do minimal research, even the icons the user above you are likely mentioning are zero excuse because the new UI supports a way of switching all of the icons with custom ones that most popular studio icon packs already support.
One of the few only valid complaints I have seen have been in @SlimenderYT’s response, and that was specifically about the quick action bar (I recall them mentioning that they were looking into reintroducing tab scrolling, and there’s a custom tab button that can be added called “UI Editor” to partially solve their other problem).