Below what i think of the series so far with these 4 episodes:
If they adapted literally the first book, the characters would be uni-dimensional and very, very boring.
What Makes the first book great are his ideas, world and universe constructions and the scientic stuffs, like psicho-Story; and the stories in first novel are very short to create a series. And because this, i expected many changes in the adaptation, specially in a series with 10 episodes. So i expected much more new material in characters like Gaal Dornick, Salvor Hardin and many many Others. And the result it´s beautiful and great, they expand the Foundation in a much larger universe and a mix of the 2 preludes of Asimov.
So yes, the series it´s great, and considering that is the irregular David Goyer as Showrunner, the Show it´s a great surprise.
P. S: If you is still pissed with the series because principally of Gender Swaps of some characters, like Demerzel or Gaal or Salvor Hardin, please go watch american football, because if you want only man, watch male sports. The first book almost don´t have women, so it´s acceptable these changes.