I do not know about the 10 million puzzle points. If it means a lot then why not. I doubt it will improve your playing that much.
99% of players struggle with these things that you mention, especially on how to think and calculate. My coach calls it the ‘algorithm’. In theory it is simple:
0. Try not to spend too much time when the move is obvious, but still think quickly.
What is the direct threat of your opponent’s move? Do I care about it?
What weakened, if any, in the opponents position due to that move?
What should I do? Checks Captures and Threats and if nothing there, what move improves my piece activity the best.
With more forcing moves, or candidate moves, evaluate to the end of the forcing line. Pick the one which seems to result in the best position
Blunder check in general and what got weakened in my position due to my move? Do I care?
Make the move
In theory, very simple and does not require grandmaster level thinking, and when applied serves very well, but in games I often simply get sucked into the gameflow and make stupid move :-)
Whatever you were, it means you were in reality playing at strength of +300 to +500 to the level of your opponents in order to be able to have a streak like that (based on probabilities).
So, go out and play. It will get only harder the longer you wait. You will likely be positively surprised. My final two cents: play 30 min rapid as that gives you maximum benefit from your tactical skills. In general it is also the best format to play if you want to develop since you can actually think through the moves good and proper.
Definitely not more than +300. I was only barely winning most of my games. I don’t have a problem with low time (Even though I either play too quickly or too slow). And I already play rated, but on an trainings account. I’ve also beaten an 1600-blitz player on that account. I would love to tag my trainings account but chess.com somehow often bugs when I try to do it. I should probably make a bug-report in Beta or something…
Also, I already told you that I struggle with my thinking process, didn’t I? If not, now you know. I usually don’t even calculate ahead or I make only brute-force calculations (Like I brute-force when doing tactics). So I don’t really use my chess knowledge during games. And so I struggle with looking at my opponent’s moves / plans. And this makes me so bad at defensive puzzles. Just saying RANDOM KING MOVES.
Btw, I really want to hit 10 million puzzle points. I would loose a lot of rating tho… Do you think it’s worth?