Being a mediocre player gets you nowhere in POE

Being a medicore player as well and had similar thoughs like the OP several times.

My observation so far: League is intense grinding non-stop. Standard often is forgotten to be the alternative.

I found myself frustrated not playing league content fast enough. If you don't want to dump more than 5-15 hours per week to play then you get litterly nowhere in league.

For that reason, I decided to play PoE at my pace accepting to miss most of the leagues' content. I even skipped many of them and played standard instead.

Standard can be fun in so many ways, in particular, if you don't want to feel the pressure of the 3-month timer running up.

If you want to play PoE like an oldschool ARPG then playing standard maybe is the answer (in particular, if you don't care about trading like me).

From one mediocre player to another, I feel your pain. My limitations are more computer based because my computer and internet are both sub par. But if you want to kill shaper my answer is always this: totems. Aw chieftain has become my go to, but there are so many good variations. Then you don't have to react as fast, very tanky too. Of course if you don't enjoy totems that doesn't help.

Another thing is that best strategy for accumulating currency isn't trying to get after end game content. It's low/mid maps very quickly. I just learned this myself. I was amazed. Make a cheap fast character capable of passing over low maps such as burial Chambers, gorge or strand really quickly. Clear as fast as you can, repeat.

Good luck to you, I hope you get some answers that help.