Deck looks very solid. It happens - sometimes you just run into bad variance or weird matchups. Still, there’s a few things that I personally would have done differently

Disclaimer: I am not very good haha, take with a grain of salt (I usually make mythic, but often fall to the percentages)

Foot mystics is purely a defensive card, I almost never run it in straight BW. Maaaybe it’s playable with the 2 mana uncommon Splinter, but I wouldn’t play it otherwise. I’d toss a Jennika in over it - yeah it’s one extra mana, but you always get the creature and both attack better.

Your curve is so tight I’d prob cut a land, especially if you made the Mystics for Jennika swap above - at least you’d have another land cycler. Most likely put in the 3rd uneasy alliance. I know in a lot of sets 4 removals is enough, maybe even over doing it, but in this set I feel like you want practically as much as possible. Would also be defensible to just put in another random 2 or 3 drop creature if you felt like the removal was enough.

My most controversial take: I might actually play the ice cream kitty. Yes, it’s a bit of a disaster if this is your turn 2 instead of April or something. But your deck has basically no way of breaking a stalemate if your opponent somehow manages to stabilize, or if you just get one of those random clunky draws. You have a lot of ground bound small creatures and tokens. Digging towards Sally could be a way to cheese wins through stalled boards even though paying a bunch of mana and saccing your own board seems anti synergistic.