The estoc was one of the stronger 2handers, especially for teamfighting, back with the old stab. Once the stab is reverted, I'm sure it'll be quite viable again. As for the blunt vs cut change, well, everyone who cared about historical accuracy instantly pointed that out to Tydeus, and his reply was "Lel, I'm sure some of them had to be edged irl so I decided to make it so based on no historical evidence."