Too many. The Decipher game, certainly, as well as the X-Wing/TIE Fighter game series. I also want the Fighter Pods back. Hate Commander. Likewise the first generation of "chibi" kids' figures. The second series weren't as fun. I want bedsheets and towels and Underoos back -- but in adult sizes, as well. I want Hasbro to stop cutting corners on plastic quality and figure accuracy. They hit a few high-water marks, and then too often fail to step up with others. Love the larger-scaled
Falcon, and accurately scaled TIE Fighter, TIE Interceptor, X-Wing, and
Slave I... but no love for the Y-Wing?

That thing hasn't had a mold update since 1977. I would also echo a plea for the return of the more "Sterling replica" version of blaster rifle, with more play features, were it not for the fact that safety-overconscious today would never let that happen.
Some of my list-toppers, though, are things that never got done -- or done right. Some ships that never got model kits, some characters that never got figures or -- worse -- got bad figures. Themes that began but have yet to be finished. Most notably, for me, are the accurately-scaled-and-marked TRU-exclusive X-Wings and Y-Wings. I would gladly shell out for the rest of Red Squadron and Golds One and Five, with accurate plots and droids. Don't know where I'd put them all, but that's a minor detail.
So yeah, short version, I want all worthwhile threads that got dropped over the years picked back up. *heh*
--Jonah