I don’t think raising bottom set multi-way is ever a mistake. When more players see the flop, it’s more likely that someone has caught enough of a piece to continue vs our raise. Although we don’t need to worry much about losing to draws when we flop this strong, we do want to consider turn cards that make it harder for one-pair type hands to play for stacks. Not the most dynamic board, but any Broadway card is a potential scare card, in addition to the spades.

I really hate slowplaying here because we are OOP and will see the turn check through somewhat frequently, allowing our opponents to fully realize their equity without paying for it (and also get away cheaply from missed draws). If we had absolute position, or at least position on the PFA, I like flatting a lot more and would probably advocate for it since the shallow SPR doesn’t require us to start building a pot now in order to get stacks in the middle. Acting after the PFA allows us to ensure there aren’t any free river cards if they slow down.

It’s always painful to flop so hard and see everyone snap fold to our raise, but I think it’s by far the best way to play our hand. I also like your sizing, I would want to go smaller (or just shove) if the only effective stack was LuckBox but I like sizing up since we are deeper with the other player.

My only concern is preflop, your open size is unusually large (you’re between 27 and 75bb effective with the table), which makes it especially awkward to call a 3bet OOP with a low pocket pair. <–  Edit: Misread the hand history, thought BB was 7500, not 10k. 

I slightly prefer folding 55 vs. a 50bb stack’s 3bet, but it’s probably fine and a small mistake at worst. IMO, you played this hand great.