All the other comments are correct, I would go farther and say it also depends on what your goal is. If you did all of them as they became available you’d level up every 8-9 days (assuming you got them all right).
I have a goal of reaching level 30 in one year, that means I have to level up every 12 days. I try to take them in groups of 30 or so, and the reviews don’t get unbearable for me, but it still isn’t actually fast enough. I’m averaging around 16 days per level, meaning around level 24-25 after a year.
So the question is, what is your goal? If it is to get to level 25 in one year, 10 a day won’t be enough. If you are happy with your rate of progression, that is what really matters because everyone will learn at different rates. If you want to go faster, take it up a notch.
