I have three favorite moments, because I can't decide which of them is my favorite. In no particular order:
1. Red Sox series. Altuve's third home run in the first game. I was there, and up near the train tracks to watch it come in. There would be a lot of great home runs in the playoffs postseason but that was so impossible and so certain at the same time.
2. Yankee series. After Verlander had struck out 13, Altuve's walkoff score from first. Again, I was there, it had already been a great game, I had perfect sightlines to watch the play develop. Taking that risk and pulling it off just summed up their play. What a great mix of they can't to they just did.
3. Game 7 Yankee series. Bregman's throw home. Just perfect in every way. Nothing in life is ever that perfect, and it was.
ETA: and I guess I utterly failed to narrow it down. I think the Altuve score from first is the one I'll remember, but the Bregman throw was so perfect. I'll go Bregman.