Regarding releases, I was mainly disappointed to only see Charizard in the XY Evolutions set, but not Venusaur and Blastoise.
Regarding personal disappointments my biggest was probably winning a Thin print 1st ed. Base Pikachu auction, which turned out to be fake on arrival… Damn I was pissed.
But let’s focus on the great moments instead, shall we? 
Always stay positive. Who knows? Maybe Blastoise and Venusaur Base artworks will be re-released as well in the near future. We never know what the future brings.
Greetz,
Quuador