Guys with brute force we won't go anywhere.
Let us assume we would be able somehow to generate a brute force of 5 TH/s (The max ASIC Miner speed today that I found out there).
That's like 5000000000000 Hashes per second. Of course with CPU/GPU we won't get anywhere near.
But let us assume for a second that this performance would be possible somehow, we would need ~303150594339750000000000000000000000000000000000000000000 years to break
until the address 256 already counting with starting each address generation from 2^X-1. (EDIT: Not even counting with all the addresses before

)
So it's kind of useless to brute force this.
Unlike hash operations, elliptic curve operations have unpredictable machine cycle count.
I would expect a single point addition operation (P
3 = P
1 + P
2) to have a very predictable machine cycle count. It should be something like:
x
3 = λ
2+a
1λ−a
2−x
1−x
2y
3 = −a
1x
3−a
3−λx
3+λx
1−y
1λ = (y
2−y
1) / (x
2−x
1)
From:
https://crypto.stanford.edu/pbc/notes/elliptic/explicit.htmlHow precise is this formula?