There was a rumour soon after the release of Republic Commando that a sequel was planned. It was going to be called Imperial Commando and set after the events of Episode III.
Hunting Jedi, shooting at rebels... this would have been awesome and I was so disappointed that nothing ever became of it all.
I think it comes down to LucasArts new Quality Control approach... after the market was flooded with 3rd party licensed Star Wars games that weren't very good, they became a bit more strict on their IP which is why SW games have been few and far between recently.
It took a while for Dark Forces to get a sequel so who knows - there's still some hope yet if the demand is there.
XBL Gold Account: MugOfRevenge
My Concept Art Blog