Here's a script i did a few years ago.  Pretty simple, just makes components perfectly planar along X,Y,Z, or an arbitrary 'best' axis
this is my attempt at mirroring the way 3ds max does it as i got pretty attached to having that tool :)

check out the readme for instructions and further details :)
i think i made it for maya 7.0+ but i don't have any versions that far back to check :(




NOTE: 'Best Plane' works best on FACE components (fyi it does an internal conversion to faces anyway)  Probably not the best way to do it :( but I haven't used maya in a while so it'll have to stay that way for now