Companions and henchmen are pretty different types of NPCs, and anyone who has actually played D:OS should have noticed this somewhere along the way.
There are lots of henchmen in the game, but currently only two companions (Madora and Jahan). There were supposed to be a few more companions, but the additional companions were postponed due to time constraints. They're supposed to be added in the months following launch.
The desire to have more companions is understandable as henchmen really don't hold a candle to them (no matter how many henchmen are available). Even the developers felt the differences were large enough to warrant making companions a funding stretch goal.
It's really not any more complicated than that. I'm not sure why this thread has stretched into a two page debate already.
