Generally my opinion on Numenera boils down to, system is great and I would love to use it more often, except its a little difficult to adapt to everything I'd like to play. The setting is a little more hit or miss, but I certainly don't hate it. (Honestly I sort of wish they gave a less defined world, if only because I prefer they leave me more room to fit more weird stuff of my own design)

That said, I certainly think its possible to make something a little more defined with the tools it offers. Once again I've been interested in playing Eberron with the Cypher system. The most work that needs to be done is adapting descriptors for the various fantasy races. As far as the numenera themselves I'm more inclined to just adapt them on the fly as they come. If the players randomly roll a cypher that detects lies by absorbing psionic energy and twitching when it hears deceptions, that's easily adapted into a medallion or something with the same effects. Meanwhile a wristband that fires a gas pellet that knocks people out is just as easily called a one-use wand of sleep. That said I'll probably put a little more work in for some of the artifacts and oddities. Artifacts because they're more permanent and so usually are just as defined by their construction as their actual effects. (For example I'm pretty sure one of the artifact examples was a cloning pod, something I'd be a little more wary about using in a fantasy world (except as maybe some sort of aberrant xoriat fleshwarping device, but it'd still take some work to get the flavor right)) Oddities because a few of them get a little too weird, for example "gloves that give the wearer a high-pitched squeaky voice." This is technically because most of these device's true purposes are likely unknown, which is why they appear to only do useless things. (For example those gloves might have been designed for a creature with non-human vocal cords so they could to speak to humans on a recognizable frequency for them, on a human it just makes them sound silly. Or it could just be that they require an unknown component that allows them to actually mimic voices instead of sounding weird.) Of course since in Eberron I'm ruling that most of the magic devices the PC's will find were likely be built by humans quite recently, there purposes will likely be much more clear, with oddities merely acting like magical art pieces or curiosities without a practical effect for adventurers. (Like a magical music box, or a silk scarf that doesn't tear or get dirty.)