Episode 3...wow. Beautiful.
To be honest, I had mixed feelings about them deviating from the game so dramatically...I was really hoping to see Nick Offerman's take on angy, jaded, talking-to-himself Bill and the utterly chaotic interactions between him and Ellie. At first I was disappointed we didn't get any of that. And this was a long episode, spending most of the runtime on characters that ultimately wouldn't have much, or any, direct impact on Joel & Ellie's story (other than the free supplies and the on-the-nose "open your heart! Save & protect those you care about, Joel! WINK WINK" line in the letter). But thinking about it in the thematic context of the show, it absolutely fits.
They took a 1 page note from the game and turned it into an entire episode of a beautiful story about how love can prevail in a dangerous and depressing world that threatens to take your humanity and leave you a shell of yourself. In a world that, as we've seen, can take everything from you, they found each other and had a better life together than they ever could have before the world fell apart. Bill and Frank didn't just survive, they lived.