I did enjoy it and would recommend it to others, although did have some reservations.
Things that bothered me a bit, off the top of my head:
.1. found the whole 'friendship will save you, even when you've be been a complete arse' idea a bit on the nose really, and didn't feel like there was enough build-up to the help from Benny and Beltik etc at the end.
2. I was really surprised to find she never paid the janitor back his $10 or got in touch with him at all, even during one of the phases where things were going well and she seemed more open and friendly to people. Made me retrospectively dislike her younger self, having assumed she must have done it off screen. Them again maybe this should actually be a positive because it fed into the poignancy of his death and her relationship with him. Idk.
3. I found her sociability seemed to vary a little bit unpredictably and not necessarily in line with the ups and downs of the story. To start with I assumed she was meant to be a bit of an Autistic savant or something, but then she started to open up a bit more and relate to people better..
So turns out she does have the ability to relate to others, she's just really rude to people sometimes even when things are going well for her. I guess that is a very subjective point and may have been me projecting things onto her, but that's how I felt.
4. The last episode felt really rushed to me. I didn't get a sense of her getting back on track before Russia, and I felt like more could have happened there.
5. I would like to have seen more of the actual chess games, and to have got more of a sense for the style of the different players etc. I'm not any good at chess, but I've watched programs in the past that still managed to present chess games in interesting and dramatic ways, so it is possible. I guess they made a stab at this by having the commentators talk through games sometimes, bit I might have enjoyed more.
For point 1, if you think about when it takes place it actually makes a bit more sense, she's an American playing the Russians, and the first one to have a real shot at beating them in their own back yard. Benny even alludes to it, saying how Americans never win as they play for themselves where the Russians are a team, so it goes a bit beyond friendship, although that is clearly a part of it.