Play whatever brings you joy.
As long as you aren't blundering in the opening, the defense you choose doesn't really matter anyway - it's a draw with best play, no matter which path up the mountain you choose.
The trick is to find the path that you enjoy hiking the most.
The only lines that you mentioned which hold up are the QGD & Gruenfeld.
So the real questions are:
Are you play to be Best? Or
Are you playing for Fun?
If your trying to beat very strong players, you need a line more solid.
If your playing for fun, you can play any of the lines you mentioned.
The answer to this is sort of complicated. I do play to achieve something in chess that is meaningful to me in the competitive sense. By that I mean winning the sort of events that are significant in the amateur chess players calendar such as a big national event like the world open and the bigger local events like the state championship. There are also some local events where I can play in the top section and take on some master level players, Most of the time though I won't be playing anyone rated above 1900.
*** On the other hand winning isn't the only thing that is important to me. The creative achievement is also important to me. i don't want to just win but do it with style. In Tal's book he says the he would rather play a game that ends in a fighting draw than win in a dry technical way. He also says he has allowed a lot of draws by trying to win with style. I don't know if I would go so far as being okay with risking a draw happening in a winning position but I kind of relate with what Tal was saying about creative achievement.
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Something else I would like to do is become the kind of player who can play pretty much any opening. I had a little adventure in this already. I used to play in the 45+45 league on the FICS server where you play one game a week for 6 weeks. The last season I played there I literally prepared a different opening every week. Many of the openings I played I played for the very first time in a serious game. Optimissed mentioned that disaster can happen if you get confused when you try to do this. That happened to me a few times that season. The most memorable was when I was paired against this 2000 rated player from China....2000 as in online rating. I had prepared the Tal line of the Caro Kann. The game was going according to theory when I suddenly forgot theory at move 10 or so. Even after a 20 minute think I wasn't able to figure things out. I got the worse position and mostly lost because of that. However, we were to play again later in the season and I managed to beat him using the benko gambit. It was the first time I ever used the Benko in a serious game. Well...to be honest I had a losing position in that game too ,but the position was complicated and I was able to pull off a swindle. Oh and there was also a game against a player from Peru where I played 1. Nf3 for the first time. I didn't decide to play 1. Nf3 until the clocks started ticking. I just had this feeling that he was going to be super prepared for my normal 1. e4 stuff so I totally improvised. It worked I was up a knight and had a passed pawn. Then I suddenly blundered the pawn and the game soon ended in a draw. Playing that kind of way was exhilarating but takes a lot of energy.
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Almost immediately after this tournament. I went off to washington DC for the Eastern Open.(december 2023) My best results there were in openings I prepared for. I played the sveshnikov for the first time and scored 2 wins with the sveshnikov. I also played the Benko 3 times and scored 50 percent with it.
Over the next year or so after the Eastern Open I barely studied openings at all. Pretty much all of my chess studying consisted of reading the articles in Chess Life. I did play in the North American Open in Las Vegas in December 2024. I did do some opening study to prepare for this event, but I didn't start my opening study until about 3 weeks before the event....even so the opening study had an effect.....the most notable was a win in the black side of the sicilian alapin, and a win with black in the closed sicilian. Something I learned from playing these big OTB events is that studying openings helps, so I kind of made it more of a focus recently,