Sorry for asking this 69 IQ question for yet another time, but I really have no idea what situation I'm in.

I started solving CF problems in a fixed difficulty range every day recently. From what I've heard, as a thumb rule you should solve X+200 (where X is your rating) difficulty problem, so I tried to solve problems rated from 2300 to 2400.

After solving a few problems, I discovered that I could solve about 90% of the problems I open. And it only costs me around 20 minutes to come up with an idea. So I think they might be too easy for me.

However, I feel that I'm usually still able to learn some new idea after I solved each problem. I enjoyed maths and construction problems more than I ever did before. Also, it's really tough for me to try 2500-2600 problems, as I can only solve 20% of them. I guess these are signs that their difficulty is probably OK.

So can anyone describe what situation I'm in and give me some help?