My biggest problem with Alternative Factor, simply, is when the admiral (sorry I haven't seen it in a while) says the effect was felt all through out the galaxy and beyond
. So, the Federation has instataneous communication through the whole galaxy and beyond? Did they switch long distance carriers? That just does not fit for me. Even the anti matter/matter problem is less of a problem for me, although it is still bad. It could be an alternate dimension where two of the same would "cancell" each other out, but that wouldn't be antimatter, so it could be just a term problem there. Doing the fall of the cliff twice was bad, too.
The beard, nuff said.
So, the regular characters did okay and were well acted, but the plot and terms and story flow weren't too good.
BTW, I don't hate it.
My biggest problem with "Plato's Stepchildren" is simply this: Dr. McCoy just whips up powerful telekinesis just like that and no one ever uses it or mentions it again.