He still has a good point. The sheer attraction of a glowing lightstick will be enough to attract everyone to those classes, not to mention every emo/wannabe bully would turn to the Sith class to role-play their dream.
If it's done well though, this could be nothing more then a temporary thing, meaning everyone would start out as a Jedi or Sith but after the game has a month or two of activity, many would realize that the class does not fit their play styles. After all, many would prefer gunning enemies from afar then charging in melee.
The most important thing here, in my opinion, is to allow bending of lore. True, Jedi are the all-around good warriors but here, they must be ''just warriors''. Neat little tricks unavailable to them, but available to other classes like say...jetpacks for bounty hunters. I know...everyone could technically equip one, but such restrictions are sometimes necessary.
We should also avoid ''counter'' classes such as Jedi hunter and such. I sort of sucks that a class would have an inherent advantage over another. I know how much whining this will cause...