I just thought of a group of positional exercises completely free, but no one uses them as far as I know.
It's called STS Strategic test Suite,
it's a group of thousands of non tactical positions used to test engines ability to make strategic decisons
They are divided into strategic themes. There is zero instruction and I don't think working through them is an efficient way to get anything but frustrated. But they are there and they are free.
I've done some on Lucas Chess-Training-long term train- Map- New map-STS
It's called STS Strategic test Suite,
it's a group of thousands of non tactical positions used to test engines ability to make strategic decisons
They are divided into strategic themes. There is zero instruction and I don't think working through them is an efficient way to get anything but frustrated. But they are there and they are free.
I've done some on Lucas Chess-Training-long term train- Map- New map-STS