Quality over Quantity.
You are studying the correct way. When i was studying seriously. Their would be times i would only get 3 tactics done in a day. But I thoroughly understood those tactics, motifs, positions, and the "why" behind how the tactic developed.
My personal view is that both approaches have their place and train different things. Taking time with complex puzzles until you're confident you have the solution trains calculation and visualization, whereas doing many simple puzzles quickly trains pattern recognition.
Then I should probably train more pattern recognition. I am terrible at playing chess quickly. I often lose, because I hit the time limit on speed chess or miscalculate under time pressure. Also... chess.com restricts how many puzzles you can do per day - even on a Gold membership. Which is really kind of depressing if you think about it, because that prohibits you from actually doing more puzzles in a quicker time frame. Lichess lets you play as many as you want for free. If chess.com wouldn't have quick analysis and a more beautiful design...
Guess I maybe have to work more on survival puzzles?
Timed puzzles would be a great idea.
As in: You get as many seconds for a task as the average user needs for the task.
I would also prefer a puzzle structure that is using the "Super Mario Effect". As in: You get puzzles and if don't you solve them, you don't lose points, you just have to repeat them later to learn the pattern and if you get the solution right, you have to do less repetitions. That way, your progress would only go up with learned patterns and you would not get punished for failing a puzzle. This would really improve motivation to learn new patterns in a shorter time frame.
At a certain point does it make sense to take a leave from I've I've plateaued around 2200 puzzle rating, which may mean that the puzzles presented above this are beyond my natural ability, my natural level of projection, concentration and possibly desire. I'm not sure that doing more puzzles makes sense. Doing them faster will just lead to errors. Slower and more intense, writing out the lines might help but may also exceed my tedium tolerance as this is something for fun and challenge. So I'm at that point and just thinking it may not get any better. Like Clint Eastwood asked "What if this is as good as it gets?". I don't play many real games as they can be nerve wracking, though prefer at least 15 min and up, usually 30... Like many things in life the Peter Principle may be in play!
Well, one thing to notice is that your average puzzle rating is not actually representative for your chess rating. For comparison, look at the best puzzle player on chess.com: alyurfed (https://www.chess.com/member/alyurfed). His chess rating is at 65334 [...].
Actually, it doesn't make sense to take a leave in my opinion. The problem is that we DO actually plateau out at a certain point, but can move past that if we sacrifice speed. The problem is purely psychological, because at some points, you are afraid of losing artifical points that actually mean NOTHING in the real world. Therefore you stop doing puzzles while you actually could learn new motifs, new tactics, new patterns and improve your play beyond your current threshold.
The puzzle rating system is broken in my opinion and does not encourage players to go beyond their current levels.
My conclusion is that the puzzle system could be improved by chess.com by either changing the current system or making more diverse offers for puzzle challenges.
I - personally - will probably check out the puzzle system on Lichess soon. Maybe the combination of the best of both websites is the best choice?
I spend a lot of time on single puzzles until I am kind of confident that I have the solution. Is this correct? What does scientific data analysis have to say about this?