In designing the set, Mark Rosewater, in the article "Outlaws of the Land, Part 1," noted this: "Defining 'commit a crime' as a type of action, something many Magic cards do, rather than as a specific new mechanic, allowed us to define the term in a way that made many existing cards part of the theme." This means that we can use cards that have existed since Alpha when looking at Crime, and focus on cards that care about Crimes being committed
Several factors influence Dragon card values: card condition (mint cards worth 3-5x more), rarity (holographic and rare cards command higher prices), first edition status, PSA/BGS grading scores, and market demand for specific Pokemon
The drawback of Spore Frog and Kami of False Hope is that your opponents will be able to see it coming
This puts them in a lose-lose situation: pay an extra mana tax on all noncreature spells or let you draw free cards