Stats could be worked on but yeah we need spirit and weapon boots for more build diversity, I also made another post about being able to upgrade Enduring Speed by combining it with either Spirit Armor or Bullet Armor
New items that take Improved Bullet / Spirit armor and Enduring Speed would be cool to free up slots in late game, maybe it would be cheap-ish and not increase the stats.
Somewhat related ( i think) when trying to wall jump, you have to be already pressing the direction key away from the wall and then press shift for it to register, but if you're holding shift already, tapping the direction key wont register a wall jump. Seems unintentional.