(Jaya Ballard, Karn, Narset, Ob Nixilis, Teferi, Urza, Venser, and Xenagos all also exist as planeswalker cards and separately as legendary creature cards.) Magic 2010 was the first core set to feature planeswalkers, but those cards were simply reprints of the Lorwyn Five
The problem is that tokens and basic lands show up in every single pack, which means their supply and prices will be heavily dictated by just how much Unstable sells overall, which in turn means any discussion of Un-set finance is built on the foundation of total demand for the product and set sales
In Modern Leyline of Resonance could also see some fringe play, but because creature removal is so efficient it is unlikely that it makes any real impact
Some of the obvious suspects were on the restricted list: the Power 9, sol ring and time vault (this was before its first errata)