A new X-Wing/Tie Fighter game would be awesome. Hell, I would be happy with just a re-release of the series with modernized graphics, an orchestrated version of the iMuse soundtracks, and full optimization for modern PCs. I spent countless hours of my childhood playing those games, and their gameplay mechanics still hold up today. I've always wanted to be Wedge Antilles more than Luke Skywalker anyway.
As for why Star Wars games are in a rut, I think it's for a few major reasons:
1. LucasArts treats the games like Lucas treats the franchise as a whole now: as nothing more than a means to an end for making money. There just isn't that same degree of care and love anymore, replacing it instead with "safe," marketable concepts that are insubstantial and shallow.
2. Focus on spectacle at the expense of gameplay and story. The Force Unleashed games are a prime example of this. Sure it can be fun for a handful of minutes to flail wildly about wrecking everything with the Force, but once the initial impact wears off you begin to realize just how loose and unwieldy the controls are. Moreover, the story ranges from predictable do downright ridiculous at times (and I won't even talk about how it makes a mockery of previously established canon).
3. Too many prequel games. Let's face it, the prequel trilogy isn't exactly loved by many people (to say nothing of the Clone Wars movie and TV show). Yet LucasArts insists on making games either set in or somehow connected to such series. With a few notable exceptions (Republic Commando, Starfighter, Battlefront), most of the "classic" games are set in the "classic" Star Wars trilogy. If you're going to make a Star Wars game, it might as well be inspired by the ones that are almost universally praised (either that, or from the KOTOR era).