That's a way to do it.....This way we don't deny the importance of opening game nor we overstate it,
I also liked your idea of listing common openings and your advice of not memorizing all opening lines.
Though I will try to apply your advice in my training as much as i can , i still don't understand what to do with familiar opening in my training time....
Make a little openingsrepertoire, and study most of all endgame. I study a lot of openings, it was an mistake! After 10 moves I have a great advantage, but than I feel uncomfortable, I didn't know how to play on. Bobby Fischer was a great endgame expert also Carlsen. You feel comfortable at the end, even two pawns down, you can sometimes draw. Everyone wants to play like Mike Tyson, but it doesn't work. You can knock down lower rating players in the first round, but to beat higher level players you have to develop a great endgames techniques. Succes!
"... Overall, I would advise most players to stick to a fairly limited range of openings, and not to worry about learning too much by heart. ... Just learn enough to get by, and spend more of your chess study time improving your tactical ability. ..." - FM Steve Giddins (2008)
Perhaps of interest:
https://www.chess.com/article/view/learning-an-opening-to-memorize-or-understand
In a 2006 GM John Nunn book, in connection with opening study, it is stated that, if a "book contains illustrative games, it is worth playing these over first", and the reader was also advised, "To begin with, only study the main lines - that will cope with 90% of your games, and you can easily fill in the unusual lines later."
"... I feel that the main reasons to buy an opening book are to give a good overview of the opening, and to explain general plans and ideas. ..." - GM John Nunn (2006)
In one of his books about an opening, GM Nigel Davies wrote (2005), "The way I suggest you study this book is to play through the main games once, relatively quickly, and then start playing the variation in actual games. Playing an opening in real games is of vital importance - without this kind of live practice it is impossible to get a 'feel' for the kind of game it leads to. There is time enough later for involvement with the details, after playing your games it is good to look up the line."
Sultan Khan (from India, and Sultan was his name, not a title) became one of the top ten players in the world in the early 1930s without ever learning any "real" openings. He just played the irregular Bishop-fianchetto systems that he had learned as a child.
In the part of rural India where he was raised, two different forms of Chess were common, and in one of them the Pawns only moved one square... there was no such thing as 1. e4 in that variant of the game. So fianchetto systems were very common: they could be played in either variant of the game, giving you a "portable" opening system.
https://en.wikipedia.org/wiki/Mir_Sultan_Khan
I never believed in learning chess from books and theory....There was no one to teach me through weekly lessons or i never try to learn new openings , but since i started to play tournaments to gain rating i started to think that am i wrong to depend on fewer familiar opening or should i expand my basic openings knowledge or should i learn more openings in depth .