flattening along normals

is there a way to flatten two faces along its normal?

the way i currently use is CTRL+ALT+SPACE and then S+Z+Z+0, but i would guess there was a tool for this. is there?

You can change the transform orientation to ‘normal’ (alt-space) instead of creating a new orientation. Other then that, it doesn’t change much from the operation you posted which is already pretty fast. You can also change the pivot point to active element if you want to align everything to the normal of one face.

LoopTools - flatten -setting either normal or best. good for when faces are not on grid planes.
Lot of good quick one click tools under one tab, bridge, to circle, curve, flatten, relax etc.
Think it’s in included addons?
https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Modeling/LoopTools