I wonder why Garak wasn't upgraded to regular status and/or Jake wasn't demoted to recurring status.
Robinson may have indicated he did not want to sign a five-year contract. (Did you know he was in competition with Stephen Collins to play Decker in TMP?)
Lofton was a child actor when he signed his five-year contract, therefore much cheaper
than the other regulars. Due to not being used often, perhaps his next two contracts were also less-generous, but the actor signed anyway?
Funny enough, whatever momentum People Magazine provided for the writers was pretty much squandered anyway.
The other Kes problem was that the actress had been "bombing" at numerous conventions. Painfully shy in real life, her often-bizarre public appearances instigated rumours of drug use. True or not, it made her a very unreliable ambassador for Star Trek.