The steam pistons, especially compared to them before the pressure update, have almost no power.

8 medium pistons can't move a fairly small vehicle, all of them are being supplied with a constant flow of steam at a more than adequate pressure. The pistons should be returned to the power output they had in the previous update, because as it stands now nearly every steam locomotive on the workshop, as well as all of my own creations, are completely useless.

Furthermore, while this isn't explicitly related to steam pistons, it is still related to steam-

The steam whistle has no particles and plays no sound when used, and particles as a whole are missing from fireboxes and simply exhausting steam.