I think Lego is stuck in a tough place right now because they don't have any new-ish material to use for desirable sets. It's one of the many kick-in-the-gonads that was the the sequel trilogy. Out of those three movies, how many ships do you remember that you would want as a set? Maybe Kylo Ren's shuttle? Maybe that big-ass ship that Laura Dern broke in two? The bigger AT-AT thingy? And then you really start scraping the bottom of the barrel, as if we weren't there already.
Compare that to the OT, and how many memorable ships/vehicles came out of those three movies. And those ships are so memorable/nostalgic/creative, we still look forward to Lego making a better version of them every now and then. The OT is getting towards being tapped, and when that happens, Lego may be hosed (to an extent). IMO, they need to start tapping into the prequel trilogy more. The kids that grew up with those movies now have disposable income, and there are a lot more interesting ships in the PT than in the ST. Personally, I'm just waiting for a UCS Sith Infiltrator. But there are several ships/vehicles from those three movies that are worth doing for the first time, or doing again, or doing better than they've been done.