I've been very conflicted about the whole "Weaponized Paradise" theme for my Great Designer Search set. On the one hand, I feel like it's a very interesting concept with a lot of depth and available design space. On the other hand, it's very open-ended and difficult to implement. Feedback has been largely positive, but I agree with the concerns that the idea may be *too* high concept. I'd even gained some confidence with a few cool mechanics, but had been struggling with whether the idea was strong enough for a set. I considered just letting the theme go despite my interest in it.
Tonight's epiphany was that the best course of action is to give a set both a textured philosophical theme and a simple mechanical one. Invasion block's themes were "an epic worldwide conflict centuries in the making" and "multicolor." Zendikar had "adventure world full of deadly peril" and "lands." Now we have Scars of Mirrodin, with "a world corrupted by ancient evil" and "artifacts."
"Weaponized paradise" is the exact theme I need to drive the flavor of the set and determine how I want it to feel. But I also need a more basic mechanical concept to ensure synergy and focus my design. "Enchanments" is a strong (if obvious) choice that evokes a certain "powerful magic we had lying around" concept, but I'm not attached to the idea yet.
I'm pretty ecstatic about this breakthrough, though, and feeling like I'm back on track.
I've put up my page on the GDS Wiki here, but it tends to update a few days behind my thought processes on this blog.